 R语言Intermediate file missing ？

R语言 Error in xls2sep(xls, sheet, verbose = verbose, ..., method = method, :
Intermediate file 'C:\Users\杨涛\AppData\Local\Temp\RtmpAjzSdd\file4b9c7d2a7745.csv' missing!这个中间文件是什么？
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 Hex Tile Equations 等式问题
 Problem Description An amusing puzzle consists of a collection of hexagonal tiles packed together with each tile showing a digit or '=' or an arithmetic operation '+', '', '*', or '/'. Consider continuous paths going through each tile exactly once, with each successive tile being an immediate neighbor of the previous tile. The object is to choose such a path so the sequence of characters on the tiles makes an acceptable equation, according to the restrictions listed below. A sequence is illustrated in each figure above. In Figure 1, if you follow the gray path from the top, the character sequence is"6/3=97". Similarly, in Figure 2, start from the bottom left 3 to get "3*21+10=73". There are a lot of potential paths through a moderate sized hex tile pattern. A puzzle player may get frustrated and want to see the answer. Your task is to automate the solution. The arrangement of hex tiles and choices of characters in each puzzle satisfy these rules: The hex pattern has an odd number of rows greater than 2. The odd numbered rows will all contain the same number of tiles. Even numbered rows will have one more hex tile than the odd numbered rows and these longer even numbered rows will stick out both to the left and the right of the odd numbered rows. 1.There is exactly one 2. '=' in the hex pattern. 3. There are no more than two '*' characters in the hex pattern. 4. There will be fewer than 14 total tiles in the hex pattern. 5.With the restrictions on allowed character sequences described below, there will be a unique acceptable solution in the hex pattern. To have an acceptable solution from the characters in some path, the expressions on each side of the equal sign must be in acceptable form and evaluate to the same numeric value. The following rules define acceptable form of the expressions on each side of the equal sign and the method of expression evaluation: 6.The operators '+', '', '*', and '/' are only considered as binary operators, so no character sequences where '+' or '' would be a unary operator are acceptable. For example "2*3=6" and "1 =5+4" are not acceptable. 7.The usual precedence of operations is not used. Instead all operations have equal precedence and operations are carried out from left to right. For example "444/2=2+3*4" is acceptable and "14=2+3*4" is not acceptable. 8.If a division operation is included, the equation can only be acceptable if the division operation works out to an exact integer result. For example "10/5=12/6" and "7+3/5=3*4/6" are acceptable. "5/2*4=10" is not acceptable because the sides would only be equal with exact mathematical calculation including an intermediate fractional result. "5/2*4=8" is not acceptable because the sides of the equation would only be equal if division were done with truncation. 9.At most two digits together are acceptable. For example, " 9. 123+1 = 124" is not acceptable. 10.A character sequences with a '0' directly followed by another digit is not acceptable. For example,"3*05=15" is not acceptable. With the assumptions above, an acceptable expression will never involve an intermediate or final arithmetic result with magnitude over three million. Input The input will consist of one to fifteen data sets, followed by a line containing only 0. The first line of a dataset contains blank separated integers r c, where r is the number of rows in the hex pattern and c is the number of entries in the odd numbered rows. The next r lines contain the characters on the hex tiles, one row per line. All hex tile characters for a row are blank separated. The lines for odd numbered rows also start with a blank, to better simulate the way the hexagons fit together. Properties 15 apply. Output There is one line of output for each data set. It is the unique acceptable equation according to rules 610 above. The line includes no spaces. Sample Input 5 1 6 / 3 = 9  7 3 3 1 + 1 * 2 0 = 3 3 7 5 2 9  * 2 = 3 4 + 8 3 4 / 0 Sample Output 6/3=97 3*21+10=73 8/4+3*92=43
 Digital Calculator 数字的计算器
 Problem Description The Advanced Calculator Machinery (ACM) is going to release a new series of calculators. Like it or not, as a member of ACM, you are asked to develop the software for the new calculator. Here is the detailed technical specification. The general usage of the calculator is that users input expressions, the calculator computes and displays the final result, or error messages if there is something wrong. The expression is in infix notation and the calculator supports following operators: People always make mistakes. When user inputs an invalid expression, the calculator should display an error message, telling user that error occurs. There are totally four possible errors: 1. Syntax error: Any kind of syntax error, such as missing operators, redundancy operators and unpaired brackets. 2. Divide by zero: The right operand of operator “/” or “%” is zero. 3. Integer overflow: At any step of the calculation, any intermediate values go beyond the range of 32bit signed integers. 4. Invalid exponent: The right operand of operator“^” is negative, or both operands are zero (we consider 0^0 undefined). The calculation works this way: at first the calculator omits all space characters of the expression, check the syntax, and then computes. It always finds the highest priority part of the expression, then operators which combines them, then calculate the result and continue the process, until the final result has been got or error occurs. For example, for expression 2^3^(4*5), there are mainly 5 steps (we use brackets to note every part of the expression): 1. Check the syntax, no syntax errors. 2. Fetch the highest priority operator 4, no errors. 3. Do arithmetic (4), get result 4, no errors. 4. Do arithmetic ((4))*(5), get result 20, no errors. 5. Because operator “^” has right associativity, we do arithmetic (3)^(((4))*(5)), e.g. (3)^(20) first. 20 is a negative number, and negative numbers are not allowed as an exponent, so the calculator simply outputs error message and stops. Notes: Because ““ has two meanings, the calculator will treat it as an unary operation at first, and if it fails, ““ would be treated as minus operation then. Write a program to simulate the calculator. Input The first line of the input file is an integer T<=200, then following T test cases. Each test case has only one line, the input expression given to the calculator. Each expression has no more than 2000 characters. Output For each test case, output one line contains the case number and the final result or “ERROR!” if any error occurs. See sample for detailed format. Sample Input 6 2^(1 2  9)^(5%3) 98**7 4%(2^01) 5%3+5%3 7^100 (73)^(37) Sample Output Case 1: 512 Case 2: ERROR! Case 3: ERROR! Case 4: 4 Case 5: ERROR! Case 6: ERROR!
 A Simple Language 表达式问题
 Problem Description Professor X teaches the C Programming language in college, but he finds it's too hard for his students and only a few students can pass the exam. So, he decide to invent a new language to reduce the burden on students. This new language only support four data type, but the syntax is an strict subset of C. It only support assignment operation, brackets operation , addition , subtration, multiplication and division between variables and numbers. The priority of operations is the same as C. In order to void the problem of forgetting the eliminator ";", this new language allow to omit it. The variable naming rules is the same as C. Comments is not allowed in this language. Now Prof.X need to impelment this language, and the variable part is done by himself. Now Prof.X need you, a execllent ACM coder's help: Given a section of this language's code, please calculate it's return value. Input The input contains many lines, each line is a section of codes written in the language described above, you can assume that all variables have been declared as int and have been set to 0 initially. Output To each line of input, output an integer indicate the return value of the input line. the semicolon will only appear in the end of line, you can assume that every literal, variable's value and the intermediate results of calculation would never bigger than a short integer. Notice: the result may affect by assignment operation, if you don't know the exact return value of some statements such as a=3, you can try run codes such as ' printf("%d",a=3); ' in C, and check the result. Sample Input a=3 a+b a=a*(b+2)+c; a+b a/4 _hello=2*a; Sample Output 3 3 6 6 1 12
 Intermediate Rounds for Multicasting
 Problem Description Consider a communication network consisting of N nodes numbered from 1 to N. The nodes are interconnected in such a way that the network has the shape of a rooted tree, with node 1 as the root. Node 1 wants to send a message (the same message) to each node which is a leaf in the tree (i.e. has no sons) – this operation is known as multicast. A message can only be sent from one node to one of its descendants (including the node itself). Each edge of the tree has an associated cost and the cost of sending a message from a node X to one of its descendants Y is the sum of the costs of the edges on the unique path from X to Y (if X=Y, then the cost is 0). The total cost of a multicast strategy is the sum of the costs of sending each message. In order to reach its goal, node 1 will use the following multicast strategy: The strategy consists of K intermediate rounds. In the first round, node 1 sends an individual message to a subset of nodes S1 such that each leaf is a descendant of exactly one node X in S1 (this means that any node X in S1 is not a descendant of another node Y in S1). In round i (2<=i<=K), each node X in Si1 sends an individual message to a subset Si,X of nodes from its subtree, such that each leaf which is a descendant of X is also a descendant of exactly one node in Si,X. The set of nodes Si is the union of the sets Si,X, for each X in Si1. In the end, each node X in Sk must send a message to each leaf node which is a descendant of X. Given the communication network, the cost of each edge and the number of intermediate rounds K, find the minimum total cost of a multicast strategy. Input The first line of input contains an integer number T, representing the number of test cases to follow. The first line of each test case contains 2 integer numbers: N (1<=N<=333) and K (1<=K<=10). The next N1 lines contain 3 integers each: A, B and C (1<=C<=10.000), meaning that node B is a son of node A and the edge (A,B) has cost C. Output For each of the T test cases, in the order given in the input, print one line containing the minimum total cost of a multicast strategy having the specified properties. Sample Input 1 6 1 1 2 10 1 3 11 2 4 21 2 5 17 3 6 7 Sample Output 66
 关于“无法解析的外部符号”与“无法解析的外部命令”
 在采用外部函数和extern变量时发生的问题 ``` #include <stdio.h>/*包含头文件*/ extern int add(); extern result(); main() { char option1,option2,option3,option4; printf("1.你会选择哪种仪式来告别一段旧恋情？\n"); printf("A.开始一段旅行，迎接新的邂逅\n"); printf("B.清理旧物，清空回忆\n"); option1 = getchar(); getchar(); printf("2.突然有帅哥/美女来搭讪，你的反应？\n"); printf("A.惊喜\n"); printf("B.惊吓\n"); option2 = getchar(); getchar(); printf("3.关于婚姻与爱情的态度？\n"); printf("A.相爱了，结婚不就是个本么？\n"); printf("B不行！结婚是终身大事，必须慎重\n"); option3 = getchar(); getchar(); printf("4.你愿意做海王吗？\n"); printf("A.坦然接受，渣一点也无妨\n"); printf("B.果断拒绝，爱的太多是灾难\n"); option4 = getchar(); getchar(); } ``` ``` #include<stdio.h> extern char option1, option2, option3, option4; int add() { int score = 0; if (option1 == 'a'  option1== 'A')score = score + 1; if (option2 == 'a'  option2 == 'A')score = score + 1; if (option3 == 'a'  option3 == 'A')score = score + 1; if (option4== 'a'  option4 == 'A')score = score + 1; return score; } ``` 此段代码报错：无法解析的外部符号option1, option2, option3, option4 ``` #include<stdio.h> extern int score; result() { if (score == 4)printf("你对待感情的态度可谓是妥妥的浪啊。因为你的不羁放纵爱自由，你在青年时期烂桃花不断；而随着年岁渐长，人老珠黄的你，也只能哀叹风光不再了！\n"); if (score == 3)printf("你放浪形骸，但不排斥过平静的生活，因此，在经过渣男/渣女的洗礼后，你也找到了自己的真爱，最终桃花结果！\n"); if (score == 2)printf("你在爱情方面比较中立，既能保持一个人的潇洒，也能享受两个人的甜蜜。你的桃花属于正常，将来很可能遇见对的人，然后相伴一生\n"); if (score == 1)printf("你有些谨慎保守哦！如果把你的同龄人比作可乐，那你就是一壶苦茶，属于徒手撕桃花的存在，不过别担心，迟来的春天总是会来的，中年成熟的魅力会让你离桃花更近一步哦！\n"); if (score == 0)printf("你...您贵庚哪？看来你已经不适合浪漫的邂逅了，不仅青年没桃花，就连中年看见小情侣秀恩爱你都会觉得肉麻，仿佛对桃花过敏！看来，你还是适合相顾相知，细水长流的黄昏恋啊\n"); } ``` 此段代码报错：无法解析的外部符号score 此外整个project有5个无法解析的外部命令 还有一个叫做Microsoft.CppBuild.targets的文件发出警告：The intermediate directory (Debug\) contains files shared from another project (Project1.vcxproj). This can lead to incorrect clean and rebuild behavior. 求指教
 Persistent Bits 实现
 Problem Description WhatNext Software creates sequence generators that they hope will produce fairly random sequences of 16bit unsigned integers in the range 0–65535. In general a sequence is specified by integers A, B, C, and S, where 1 ≤ A < 32768, 0 ≤ B < 65536, 2 ≤ C < 65536, and 0 ≤ S < C. S is the first element (the seed) of the sequence, and each later element is generated from the previous element. If X is an element of the sequence, then the next element is (A * X + B) % C where '%' is the remainder or modulus operation. Although every element of the sequence will be a 16bit unsigned integer less than 65536, the intermediate result A * X + B may be larger, so calculations should be done with a 32bit int rather than a 16bit short to ensure accurate results. Some values of the parameters produce better sequences than others. The most embarrassing sequences to WhatNext Software are ones that never change one or more bits. A bit that never changes throughout the sequence is persistent. Ideally, a sequence will have no persistent bits. Your job is to test a sequence and determine which bits are persistent. For example, a particularly bad choice is A = 2, B = 5, C = 18, and S = 3. It produces the sequence 3, (2*3+5)%18 = 11, (2*11+5)%18 = 9, (2*9+5)%18 = 5, (2*5+5)%18 = 15, (2*15+5)%18 = 17, then (2*17+5)%18 = 3 again, and we're back at the beginning. So the sequence repeats the the same six values over and over: Decimal 16Bit Binary 3 0000000000000011 11 0000000000001011 9 0000000000001001 5 0000000000000101 15 0000000000001111 17 0000000000010001 overall 00000000000????1 The last line of the table indicates which bit positions are always 0, always 1, or take on both values in the sequence. Note that 12 of the 16 bits are persistent. (Good random sequences will have no persistent bits, but the converse is not necessarily true. For example, the sequence defined by A = 1, B = 1, C = 64000, and S = 0 has no persistent bits, but it's also not random: it just counts from 0 to 63999 before repeating.) Note that a sequence does not need to return to the seed: with A = 2, B = 0, C = 16, and S = 2, the sequence goes 2, 4, 8, 0, 0, 0, .... Input There are from one to sixteen datasets followed by a line containing only 0. Each dataset is a line containing decimal integer values for A, B, C, and S, separated by single blanks. Output There is one line of output for each data set, each containing 16 characters, either '1', '0', or '?' for each of the 16 bits in order, with the most significant bit first, with '1' indicating the corresponding bit is always 1, '0' meaning the corresponding bit is always 0, and '?' indicating the bit takes on values of both 0 and 1 in the sequence. Sample Input 2 5 18 3 1 1 64000 0 2 0 16 2 256 85 32768 21845 1 4097 32776 248 0 Sample Output 00000000000????1 ???????????????? 000000000000???0 0101010101010101 0???000011111???
 Jimmy’s travel plan 怎么来编写
 Problem Description Jimmy lives in a huge kingdom which contains lots of beautiful cities. He also loves traveling very much, and even would like to visit each city in the country. Jaddy, his secretary, is now helping him to plan the routes, however, Jaddy suddenly find that is quite a tough task because it is possible for Jimmy to ask route’s information toward any city. What was worth? Jaddy has to response for queries about the distance information nearly between any pair of cities due to the undeterminable starting city which Jimmy is living in when he raises a query. Because of the large scale of the whole country, Jaddy feel hopeless to archive such an impossible job, however, in order to gratify his manager, Jaddy is now looking forward to your assistance. There might be good news about Jaddy’s work: since Jimmy is very lazy and would not like to travel to a destination whose distance between the original city is larger than TWO. That means only one intermediate city among the route is acceptable (Apparently, all the connecting paths between any two cities, if exists, have the same length as ONE). But don’t be fooled: Jimmy also needs to know that how many alternative different routes are available so that he can have more options. In particular two routes were named as different if and only if there is at least one path in the two routes is distinguishable, moreover, if more than one paths exist between a particular pair of cities, they are considered as distinct. Input Input has multiple test cases. The first line of the input has a single integer T indication the number of test cases, then each test case following. For each test case, the first line contains two integers N and M indication the number of cities and paths in the country. Then M lines are following, each line contains a pair of integers A and B, separated by space, denoting an undirected path between city A and city B, all the cities are numbered from 1 to N. Then a new line contains a single integer Q, which means there are Q queries following. Each query contains a couple of integers A and B which means querying the distance and number of shortest routes between city A and B, each query occupy a single line separately. All the test cases are separated by a single blank line. You can assume that N, Q <= 100000, M <= 200000. Output For each test case, firstly output a single line contains the case number, then Q lines for the response to queries with the same order in the input. For each query, if there exists at least one routes with length no longer than TWO, then output two integer separated by a single space, the former is the distance (shortest) of routes and the later means how many different shortest routes Jimmy can choose; otherwise, output a single line contains “The pair of cities are not connected or too far away.” (quotes for clarifying). See the sample data carefully for further details. Sample Input 2 5 7 1 2 2 3 3 4 4 5 2 5 2 4 1 2 4 1 4 1 2 5 3 5 4 2 0 2 1 1 1 2 Sample Output Case #1: 2 2 1 2 2 2 1 1 Case #2: 0 1 The pair of cities are not connected or too far away.
 Persistent Bits 怎么写得呢
 Problem Description WhatNext Software creates sequence generators that they hope will produce fairly random sequences of 16bit unsigned integers in the range 0–65535. In general a sequence is specified by integers A, B, C, and S, where 1 ≤ A < 32768, 0 ≤ B < 65536, 2 ≤ C < 65536, and 0 ≤ S < C. S is the first element (the seed) of the sequence, and each later element is generated from the previous element. If X is an element of the sequence, then the next element is (A * X + B) % C where '%' is the remainder or modulus operation. Although every element of the sequence will be a 16bit unsigned integer less than 65536, the intermediate result A * X + B may be larger, so calculations should be done with a 32bit int rather than a 16bit short to ensure accurate results. Some values of the parameters produce better sequences than others. The most embarrassing sequences to WhatNext Software are ones that never change one or more bits. A bit that never changes throughout the sequence is persistent. Ideally, a sequence will have no persistent bits. Your job is to test a sequence and determine which bits are persistent. For example, a particularly bad choice is A = 2, B = 5, C = 18, and S = 3. It produces the sequence 3, (2*3+5)%18 = 11, (2*11+5)%18 = 9, (2*9+5)%18 = 5, (2*5+5)%18 = 15, (2*15+5)%18 = 17, then (2*17+5)%18 = 3 again, and we're back at the beginning. So the sequence repeats the the same six values over and over: Decimal 16Bit Binary 3 0000000000000011 11 0000000000001011 9 0000000000001001 5 0000000000000101 15 0000000000001111 17 0000000000010001 overall 00000000000????1 The last line of the table indicates which bit positions are always 0, always 1, or take on both values in the sequence. Note that 12 of the 16 bits are persistent. (Good random sequences will have no persistent bits, but the converse is not necessarily true. For example, the sequence defined by A = 1, B = 1, C = 64000, and S = 0 has no persistent bits, but it's also not random: it just counts from 0 to 63999 before repeating.) Note that a sequence does not need to return to the seed: with A = 2, B = 0, C = 16, and S = 2, the sequence goes 2, 4, 8, 0, 0, 0, .... Input There are from one to sixteen datasets followed by a line containing only 0. Each dataset is a line containing decimal integer values for A, B, C, and S, separated by single blanks. Output There is one line of output for each data set, each containing 16 characters, either '1', '0', or '?' for each of the 16 bits in order, with the most significant bit first, with '1' indicating the corresponding bit is always 1, '0' meaning the corresponding bit is always 0, and '?' indicating the bit takes on values of both 0 and 1 in the sequence. Sample Input 2 5 18 3 1 1 64000 0 2 0 16 2 256 85 32768 21845 1 4097 32776 248 0 Sample Output 00000000000????1 ???????????????? 000000000000???0 0101010101010101 0???000011111???
 C语言，Galactic Import
 Description With the introduction of the new ThrustoZoom gigadimensional drive, it has become possible for HyperCommodities, the import/export conglomerate from New Jersey, to begin trading with even the most remote galaxies in the universe. HyperCommodities wants to import goods from some of the galaxies in the Plural Z sector. Planets within these galaxies export valuable products and raw materials like vacuuseal, transparent aluminum, digraphite, and quantum steel. Preliminary reports have revealed the following facts: Each galaxy contains at least one and at most 26 planets. Each planet within a galaxy is identified by a unique letter from A to Z. Each planet specializes in the production and export of one good. Different planets within the same galaxy export different goods. Some pairs of planets are connected by hyperspace shipping lines. If planets A and B are connected, they can trade goods freely. If planet C is connected to B but not to A, then A and C can still trade goods with each other through B, but B keeps 5% of the shipment as a shipping fee. (Thus A only receives 95% of what C shipped, and C receives only 95% of what A shipped.) In general, any two planets can trade goods as long as they are connected by some set of shipping lines, but each intermediate planet along the shipping route keeps 5% of what it shipped (which is not necessarily equal to 5% of the original shipment). At least one planet in each galaxy is willing to open a ThrustoZoom shipping line to Earth. A ThrustoZoom line is the same as any other shipping line within the galaxy, as far as business is concerned. For example, if planet K opens a ThrustoZoom line to Earth, then the Earth can trade goods freely with K, or it can trade goods with any planet connected to K, subject to the usual shipping fees. HyperCommodities has assigned a relative value (a positive real number less than 10) to each planet's chief export. The higher the number, the more valuable the product. More valuable products can be resold with a higher profit margin in domestic markets. The problem is to determine which planet has the most valuable export when shipping fees are taken into account. Input The input consists of one or more galaxy descriptions. Each galaxy description begins with a line containing an integer N which specifies the number of planets in the galaxy. The next N lines contain descriptions of each planet, which consist of: The letter used to represent the planet. A space. The relative value of the planet's export, in the form d.dd. A space. A string containing letters and/or the character `*'; a letter indicates a shipping line to that planet, and a `*' indicates a willingness to open a ThrustoZoom shipping line to Earth. Output For each galaxy description, output a single line which reads "Import from P" where P is the letter of the planet with the most valuable export, once shipping fees have been taken into account. (If more than one planet have the same most valuable export value then output the plant which is alphabetically first). Sample Input 1 F 0.81 * 5 E 0.01 *A D 0.01 A* C 0.01 *A A 1.00 EDCB B 0.01 A* 10 S 2.23 Q* A 9.76 C K 5.88 MI E 7.54 GC M 5.01 OK G 7.43 IE I 6.09 KG C 8.42 EA O 4.55 QM Q 3.21 SO Sample Output Import from F Import from A Import from A
 C语言解答，Hex Tile Equations
 Problem Description An amusing puzzle consists of a collection of hexagonal tiles packed together with each tile showing a digit or '=' or an arithmetic operation '+', '', '*', or '/'. Consider continuous paths going through each tile exactly once, with each successive tile being an immediate neighbor of the previous tile. The object is to choose such a path so the sequence of characters on the tiles makes an acceptable equation, according to the restrictions listed below. A sequence is illustrated in each figure above. In Figure 1, if you follow the gray path from the top, the character sequence is"6/3=97". Similarly, in Figure 2, start from the bottom left 3 to get "3*21+10=73". There are a lot of potential paths through a moderate sized hex tile pattern. A puzzle player may get frustrated and want to see the answer. Your task is to automate the solution. The arrangement of hex tiles and choices of characters in each puzzle satisfy these rules: The hex pattern has an odd number of rows greater than 2. The odd numbered rows will all contain the same number of tiles. Even numbered rows will have one more hex tile than the odd numbered rows and these longer even numbered rows will stick out both to the left and the right of the odd numbered rows. 1.There is exactly one 2. '=' in the hex pattern. 3. There are no more than two '*' characters in the hex pattern. 4. There will be fewer than 14 total tiles in the hex pattern. 5.With the restrictions on allowed character sequences described below, there will be a unique acceptable solution in the hex pattern. To have an acceptable solution from the characters in some path, the expressions on each side of the equal sign must be in acceptable form and evaluate to the same numeric value. The following rules define acceptable form of the expressions on each side of the equal sign and the method of expression evaluation: 6.The operators '+', '', '*', and '/' are only considered as binary operators, so no character sequences where '+' or '' would be a unary operator are acceptable. For example "2*3=6" and "1 =5+4" are not acceptable. 7.The usual precedence of operations is not used. Instead all operations have equal precedence and operations are carried out from left to right. For example "444/2=2+3*4" is acceptable and "14=2+3*4" is not acceptable. 8.If a division operation is included, the equation can only be acceptable if the division operation works out to an exact integer result. For example "10/5=12/6" and "7+3/5=3*4/6" are acceptable. "5/2*4=10" is not acceptable because the sides would only be equal with exact mathematical calculation including an intermediate fractional result. "5/2*4=8" is not acceptable because the sides of the equation would only be equal if division were done with truncation. 9.At most two digits together are acceptable. For example, " 9. 123+1 = 124" is not acceptable. 10.A character sequences with a '0' directly followed by another digit is not acceptable. For example,"3*05=15" is not acceptable. With the assumptions above, an acceptable expression will never involve an intermediate or final arithmetic result with magnitude over three million. Input The input will consist of one to fifteen data sets, followed by a line containing only 0. The first line of a dataset contains blank separated integers r c, where r is the number of rows in the hex pattern and c is the number of entries in the odd numbered rows. The next r lines contain the characters on the hex tiles, one row per line. All hex tile characters for a row are blank separated. The lines for odd numbered rows also start with a blank, to better simulate the way the hexagons fit together. Properties 15 apply. Output There is one line of output for each data set. It is the unique acceptable equation according to rules 610 above. The line includes no spaces. Sample Input 5 1 6 / 3 = 9  7 3 3 1 + 1 * 2 0 = 3 3 7 5 2 9  * 2 = 3 4 + 8 3 4 / 0 Sample Output 6/3=97 3*21+10=73 8/4+3*92=43
 表达式的公式的计算的问题，怎么实现，用C语言
 Problem Description The Advanced Calculator Machinery (ACM) is going to release a new series of calculators. Like it or not, as a member of ACM, you are asked to develop the software for the new calculator. Here is the detailed technical specification. The general usage of the calculator is that users input expressions, the calculator computes and displays the final result, or error messages if there is something wrong. The expression is in infix notation and the calculator supports following operators: People always make mistakes. When user inputs an invalid expression, the calculator should display an error message, telling user that error occurs. There are totally four possible errors: 1. Syntax error: Any kind of syntax error, such as missing operators, redundancy operators and unpaired brackets. 2. Divide by zero: The right operand of operator “/” or “%” is zero. 3. Integer overflow: At any step of the calculation, any intermediate values go beyond the range of 32bit signed integers. 4. Invalid exponent: The right operand of operator“^” is negative, or both operands are zero (we consider 0^0 undefined). The calculation works this way: at first the calculator omits all space characters of the expression, check the syntax, and then computes. It always finds the highest priority part of the expression, then operators which combines them, then calculate the result and continue the process, until the final result has been got or error occurs. For example, for expression 2^3^(4*5), there are mainly 5 steps (we use brackets to note every part of the expression): 1. Check the syntax, no syntax errors. 2. Fetch the highest priority operator 4, no errors. 3. Do arithmetic (4), get result 4, no errors. 4. Do arithmetic ((4))*(5), get result 20, no errors. 5. Because operator “^” has right associativity, we do arithmetic (3)^(((4))*(5)), e.g. (3)^(20) first. 20 is a negative number, and negative numbers are not allowed as an exponent, so the calculator simply outputs error message and stops. Notes: Because ““ has two meanings, the calculator will treat it as an unary operation at first, and if it fails, ““ would be treated as minus operation then. Write a program to simulate the calculator. Input The first line of the input file is an integer T<=200, then following T test cases. Each test case has only one line, the input expression given to the calculator. Each expression has no more than 2000 characters. Output For each test case, output one line contains the case number and the final result or “ERROR!” if any error occurs. See sample for detailed format. Sample Input 6 2^(1 2  9)^(5%3) 98**7 4%(2^01) 5%3+5%3 7^100 (73)^(37) Sample Output Case 1: 512 Case 2: ERROR! Case 3: ERROR! Case 4: 4 Case 5: ERROR! Case 6: ERROR!
 遇到了"无法解析的外部符号 _mainCRTStartup", 但是第二次编译就好了
 最近突然遇到了很奇怪的问题, 开发环境是VS2019, Qt5.9.6 经常性的在重新编译的时候出现“LINK : error LNK2001: 无法解析的外部符号 \_mainCRTStartup” 可是一旦再次编译（不使用重新编译）， 该错误就会消失了。 不仅仅是可执行工程, dll也会遇到“LINK : error LNK2001: 无法解析的外部符号 \_\_DllMainCRTStartup@12” 同样, 只要不是重新编译, 选择再次编译问题就会消失 百思不得其解，虽然不影响手动编译，但是自动化编译完全就做不了了。希望高手能够解决。 链接器的所有选项如下： dll的 ``` /OUT:"D:\GIT\xxxx\bin\BasicDataManager.dll" /MANIFEST /NXCOMPAT /PDB:"D:\GIT\xxxx\bin\BasicDataManager.pdb" /DYNAMICBASE "D:\Qt\Qt\5.9.6\msvc2015\lib\qtmain.lib" "shell32.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Gui.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Sql.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Core.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /IMPLIB:"D:\GIT\xxxx\lib\BasicDataManager.lib" /DEBUG /DLL /MACHINE:X86 /SAFESEH /PGD:"D:\GIT\xxxx\bin\BasicDataManager.pgd" /SUBSYSTEM:WINDOWS /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /ManifestFile:"Release\BasicDataManager.dll.intermediate.manifest" /ERRORREPORT:PROMPT /NOLOGO /LIBPATH:"D:\Qt\Qt\5.9.6\msvc2015\lib" /LIBPATH:"C:\opensslx86\lib" /LIBPATH:"C:\Utils\my_sql\my_sqlx86\lib" /LIBPATH:"C:\Utils\postgresqlx86\pgsql\lib" /TLBID:1 ``` exe的 ``` /OUT:"D:\GIT\xxxx\bin\BasicDataManagerUI.exe" /MANIFEST /NXCOMPAT /PDB:"D:\GIT\xxxx\bin\BasicDataManagerUI.pdb" /DYNAMICBASE "BasicDataManager.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\qtmain.lib" "shell32.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Charts.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Widgets.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Gui.lib" "D:\Qt\Qt\5.9.6\msvc2015\lib\Qt5Core.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /DEBUG /MACHINE:X86 /SAFESEH /PGD:"D:\GIT\xxxx\bin\BasicDataManagerUI.pgd" /SUBSYSTEM:CONSOLE /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /ManifestFile:"Release\BasicDataManagerUI.exe.intermediate.manifest" /ERRORREPORT:PROMPT /NOLOGO /LIBPATH:"D:\Qt\Qt\5.9.6\msvc2015\lib" /LIBPATH:"D:\GIT\xxxx\lib" /LIBPATH:"C:\opensslx86\lib" /LIBPATH:"C:\Utils\my_sql\my_sqlx86\lib" /LIBPATH:"C:\Utils\postgresqlx86\pgsql\lib" /TLBID:1 ```
 C语言， Jack and Jill
 Description Ever since the incident on the hill, Jack and Jill dislike each other and wish to remain as distant as possible. Jack and Jill must attend school each day; Jack attends a boys' school while Jill attends a girls' school. Both schools start at the same time. You have been retained by their lawyers to arrange routes and a schedule that Jack and Jill will adhere to so as to maximize the closest straightline distance between them at any time during their trip to school. Jack and Jill live in a town laid out as an n by n square grid (n <= 30). It takes 1 minute to walk from one location to an adjacent location. In maximizing the distance between Jack and Jill you need consider only the distance between the locations they visit (i.e. you need not consider any intermediate points on the path they take from grid location to grid location). Some locations are impassable due to being occupied by rivers, buildings, etc. Jack must start at his house and walk continuously until he gets to school. Jill must start at her house at the same time as Jack and walk continuously until she arrives at her school. Jack's house and school are impassable to Jill while Jill's house and school are impassable to Jack. Other grid locations that are impassable to both Jack and Jill are given in the input. Input Input will consist of several test cases. Each test case will consist of n, followed by n lines with n characters representing a map of the town. In the map, Jack's house is represented by 'H', Jack's school is represented by 'S', Jill's house is represented by 'h', Jill's school is represented by 's', impassable locations are represented by '*', and all other locations are represented by '.' You may assume the normal cartographic convention that North is at the top of the page and West is to the left. A line containing 0 follows the last case. Output For each input case you should give three lines of output containing: the closest that Jack and Jill come during the schedule (to 2 decimal places) Jack's route Jill's route. Each route is a sequence of directions that Jack or Jill should follow for each minute from the start time until arriving at school. Each direction is one of 'N', 'S', 'E', or 'W'. If several pairs of routes are possible, any one will do. You may assume there is at least one solution. Leave a blank line between the output for successive cases. Sample Input 10 .......... ...H...... .**...s... .**....... .**....... .**....... .**....... .**....... ...S..h..* .......... 0 Sample Output 6.71 WWWSSSSSSSEEE NEEENNNNNWWW
 Persistent Bits 二进制的问题
 Problem Description WhatNext Software creates sequence generators that they hope will produce fairly random sequences of 16bit unsigned integers in the range 0–65535. In general a sequence is specified by integers A, B, C, and S, where 1 ≤ A < 32768, 0 ≤ B < 65536, 2 ≤ C < 65536, and 0 ≤ S < C. S is the first element (the seed) of the sequence, and each later element is generated from the previous element. If X is an element of the sequence, then the next element is (A * X + B) % C where '%' is the remainder or modulus operation. Although every element of the sequence will be a 16bit unsigned integer less than 65536, the intermediate result A * X + B may be larger, so calculations should be done with a 32bit int rather than a 16bit short to ensure accurate results. Some values of the parameters produce better sequences than others. The most embarrassing sequences to WhatNext Software are ones that never change one or more bits. A bit that never changes throughout the sequence is persistent. Ideally, a sequence will have no persistent bits. Your job is to test a sequence and determine which bits are persistent. For example, a particularly bad choice is A = 2, B = 5, C = 18, and S = 3. It produces the sequence 3, (2*3+5)%18 = 11, (2*11+5)%18 = 9, (2*9+5)%18 = 5, (2*5+5)%18 = 15, (2*15+5)%18 = 17, then (2*17+5)%18 = 3 again, and we're back at the beginning. So the sequence repeats the the same six values over and over: Decimal 16Bit Binary 3 0000000000000011 11 0000000000001011 9 0000000000001001 5 0000000000000101 15 0000000000001111 17 0000000000010001 overall 00000000000????1 The last line of the table indicates which bit positions are always 0, always 1, or take on both values in the sequence. Note that 12 of the 16 bits are persistent. (Good random sequences will have no persistent bits, but the converse is not necessarily true. For example, the sequence defined by A = 1, B = 1, C = 64000, and S = 0 has no persistent bits, but it's also not random: it just counts from 0 to 63999 before repeating.) Note that a sequence does not need to return to the seed: with A = 2, B = 0, C = 16, and S = 2, the sequence goes 2, 4, 8, 0, 0, 0, .... Input There are from one to sixteen datasets followed by a line containing only 0. Each dataset is a line containing decimal integer values for A, B, C, and S, separated by single blanks. Output There is one line of output for each data set, each containing 16 characters, either '1', '0', or '?' for each of the 16 bits in order, with the most significant bit first, with '1' indicating the corresponding bit is always 1, '0' meaning the corresponding bit is always 0, and '?' indicating the bit takes on values of both 0 and 1 in the sequence. Sample Input 2 5 18 3 1 1 64000 0 2 0 16 2 256 85 32768 21845 1 4097 32776 248 0 Sample Output 00000000000????1 ???????????????? 000000000000???0 0101010101010101 0???000011111???
 Persistent Bits 实现的方法
 Problem Description WhatNext Software creates sequence generators that they hope will produce fairly random sequences of 16bit unsigned integers in the range 0–65535. In general a sequence is specified by integers A, B, C, and S, where 1 ≤ A < 32768, 0 ≤ B < 65536, 2 ≤ C < 65536, and 0 ≤ S < C. S is the first element (the seed) of the sequence, and each later element is generated from the previous element. If X is an element of the sequence, then the next element is (A * X + B) % C where '%' is the remainder or modulus operation. Although every element of the sequence will be a 16bit unsigned integer less than 65536, the intermediate result A * X + B may be larger, so calculations should be done with a 32bit int rather than a 16bit short to ensure accurate results. Some values of the parameters produce better sequences than others. The most embarrassing sequences to WhatNext Software are ones that never change one or more bits. A bit that never changes throughout the sequence is persistent. Ideally, a sequence will have no persistent bits. Your job is to test a sequence and determine which bits are persistent. For example, a particularly bad choice is A = 2, B = 5, C = 18, and S = 3. It produces the sequence 3, (2*3+5)%18 = 11, (2*11+5)%18 = 9, (2*9+5)%18 = 5, (2*5+5)%18 = 15, (2*15+5)%18 = 17, then (2*17+5)%18 = 3 again, and we're back at the beginning. So the sequence repeats the the same six values over and over: Decimal 16Bit Binary 3 0000000000000011 11 0000000000001011 9 0000000000001001 5 0000000000000101 15 0000000000001111 17 0000000000010001 overall 00000000000????1 The last line of the table indicates which bit positions are always 0, always 1, or take on both values in the sequence. Note that 12 of the 16 bits are persistent. (Good random sequences will have no persistent bits, but the converse is not necessarily true. For example, the sequence defined by A = 1, B = 1, C = 64000, and S = 0 has no persistent bits, but it's also not random: it just counts from 0 to 63999 before repeating.) Note that a sequence does not need to return to the seed: with A = 2, B = 0, C = 16, and S = 2, the sequence goes 2, 4, 8, 0, 0, 0, .... Input There are from one to sixteen datasets followed by a line containing only 0. Each dataset is a line containing decimal integer values for A, B, C, and S, separated by single blanks. Output There is one line of output for each data set, each containing 16 characters, either '1', '0', or '?' for each of the 16 bits in order, with the most significant bit first, with '1' indicating the corresponding bit is always 1, '0' meaning the corresponding bit is always 0, and '?' indicating the bit takes on values of both 0 and 1 in the sequence. Sample Input 2 5 18 3 1 1 64000 0 2 0 16 2 256 85 32768 21845 1 4097 32776 248 0 Sample Output 00000000000????1 ???????????????? 000000000000???0 0101010101010101 0???000011111???
 编写程序来模拟计算器，运算符二义定义的解决，怎么采用C语言的程序的编写的过程的思想呢
 Problem Description The Advanced Calculator Machinery (ACM) is going to release a new series of calculators. Like it or not, as a member of ACM, you are asked to develop the software for the new calculator. Here is the detailed technical specification. The general usage of the calculator is that users input expressions, the calculator computes and displays the final result, or error messages if there is something wrong. The expression is in infix notation and the calculator supports following operators: People always make mistakes. When user inputs an invalid expression, the calculator should display an error message, telling user that error occurs. There are totally four possible errors: 1. Syntax error: Any kind of syntax error, such as missing operators, redundancy operators and unpaired brackets. 2. Divide by zero: The right operand of operator “/” or “%” is zero. 3. Integer overflow: At any step of the calculation, any intermediate values go beyond the range of 32bit signed integers. 4. Invalid exponent: The right operand of operator“^” is negative, or both operands are zero (we consider 0^0 undefined). The calculation works this way: at first the calculator omits all space characters of the expression, check the syntax, and then computes. It always finds the highest priority part of the expression, then operators which combines them, then calculate the result and continue the process, until the final result has been got or error occurs. For example, for expression 2^3^(4*5), there are mainly 5 steps (we use brackets to note every part of the expression): 1. Check the syntax, no syntax errors. 2. Fetch the highest priority operator 4, no errors. 3. Do arithmetic (4), get result 4, no errors. 4. Do arithmetic ((4))*(5), get result 20, no errors. 5. Because operator “^” has right associativity, we do arithmetic (3)^(((4))*(5)), e.g. (3)^(20) first. 20 is a negative number, and negative numbers are not allowed as an exponent, so the calculator simply outputs error message and stops. Notes: Because ““ has two meanings, the calculator will treat it as an unary operation at first, and if it fails, ““ would be treated as minus operation then. Write a program to simulate the calculator. Input The first line of the input file is an integer T<=200, then following T test cases. Each test case has only one line, the input expression given to the calculator. Each expression has no more than 2000 characters. Output For each test case, output one line contains the case number and the final result or “ERROR!” if any error occurs. See sample for detailed format. Sample Input 6 2^(1 2  9)^(5%3) 98**7 4%(2^01) 5%3+5%3 7^100 (73)^(37) Sample Output Case 1: 512 Case 2: ERROR! Case 3: ERROR! Case 4: 4 Case 5: ERROR! Case 6: ERROR!
 Hex Tile Equations 方程问题
 Problem Description An amusing puzzle consists of a collection of hexagonal tiles packed together with each tile showing a digit or '=' or an arithmetic operation '+', '', '*', or '/'. Consider continuous paths going through each tile exactly once, with each successive tile being an immediate neighbor of the previous tile. The object is to choose such a path so the sequence of characters on the tiles makes an acceptable equation, according to the restrictions listed below. A sequence is illustrated in each figure above. In Figure 1, if you follow the gray path from the top, the character sequence is"6/3=97". Similarly, in Figure 2, start from the bottom left 3 to get "3*21+10=73". There are a lot of potential paths through a moderate sized hex tile pattern. A puzzle player may get frustrated and want to see the answer. Your task is to automate the solution. The arrangement of hex tiles and choices of characters in each puzzle satisfy these rules: The hex pattern has an odd number of rows greater than 2. The odd numbered rows will all contain the same number of tiles. Even numbered rows will have one more hex tile than the odd numbered rows and these longer even numbered rows will stick out both to the left and the right of the odd numbered rows. 1.There is exactly one 2. '=' in the hex pattern. 3. There are no more than two '*' characters in the hex pattern. 4. There will be fewer than 14 total tiles in the hex pattern. 5.With the restrictions on allowed character sequences described below, there will be a unique acceptable solution in the hex pattern. To have an acceptable solution from the characters in some path, the expressions on each side of the equal sign must be in acceptable form and evaluate to the same numeric value. The following rules define acceptable form of the expressions on each side of the equal sign and the method of expression evaluation: 6.The operators '+', '', '*', and '/' are only considered as binary operators, so no character sequences where '+' or '' would be a unary operator are acceptable. For example "2*3=6" and "1 =5+4" are not acceptable. 7.The usual precedence of operations is not used. Instead all operations have equal precedence and operations are carried out from left to right. For example "444/2=2+3*4" is acceptable and "14=2+3*4" is not acceptable. 8.If a division operation is included, the equation can only be acceptable if the division operation works out to an exact integer result. For example "10/5=12/6" and "7+3/5=3*4/6" are acceptable. "5/2*4=10" is not acceptable because the sides would only be equal with exact mathematical calculation including an intermediate fractional result. "5/2*4=8" is not acceptable because the sides of the equation would only be equal if division were done with truncation. 9.At most two digits together are acceptable. For example, " 9. 123+1 = 124" is not acceptable. 10.A character sequences with a '0' directly followed by another digit is not acceptable. For example,"3*05=15" is not acceptable. With the assumptions above, an acceptable expression will never involve an intermediate or final arithmetic result with magnitude over three million. Input The input will consist of one to fifteen data sets, followed by a line containing only 0. The first line of a dataset contains blank separated integers r c, where r is the number of rows in the hex pattern and c is the number of entries in the odd numbered rows. The next r lines contain the characters on the hex tiles, one row per line. All hex tile characters for a row are blank separated. The lines for odd numbered rows also start with a blank, to better simulate the way the hexagons fit together. Properties 15 apply. Output There is one line of output for each data set. It is the unique acceptable equation according to rules 610 above. The line includes no spaces. Sample Input 5 1 6 / 3 = 9  7 3 3 1 + 1 * 2 0 = 3 3 7 5 2 9  * 2 = 3 4 + 8 3 4 / 0 Sample Output 6/3=97 3*21+10=73 8/4+3*92=43
 输入字符串构建两个二叉搜索树
 A tempting approach to maintaining a balanced binary search tree is to maintain two binary search trees and to insert each new key into the tree that will be more balanced. More specifically, do the following: The first key is the root of the left tree. The second key is the root of the right tree. To add a new key, insert it into the tree where it would have a smaller depth. If the depths of both trees are the same, then add it to the first tree.The input will be 5 strings (ignore everything but the letters A through Z and a through z; uppercase and lowercase are the same). For each input string, build the two trees with each string as described above. Print contents of the first tree in preorder (root, then the left child, then the right child). Sample Input: Line #1: AMERICAN COMPUTER SCIENCE Line #2: I must say that I find television very educational Line #3: INTERMEDIATE DIVISION Sample Output: Output #1: A A E C C E E N I P S Output #2: I A A A A I D D C E E I U T T S R U Y V Y Output #3: I E E A I I I T T V 维护一个平衡的二叉搜索树的一个诱人的方法是维护两个二叉搜索树，并将每个新键插入树中，这样会更加平衡。更具体地说，执行以下操作:第一个键是左树的根。第二个键是右树的根。若要添加新键，请将其插入到树中其深度较小的位置。如果两棵树的深度相同，则将其添加到第一棵树上。 输入将是5个字符串(忽略除了字母A到Z和A到Z;大写和小写是一样的)。对于每个输入字符串，使用上面描述的每个字符串构建两个树。按顺序打印第一个树的内容(根，然后左子树，然后右子树)。 样例输入: 第一行:美国计算机科学 我得说我觉得电视很有教育意义 第3行:中间部分 样例输出: 输出#1:A A E C C E E N I P S 输出#2:I A A A I D D C E E I U T S R U Y V Y 输出#3:ieia I I T T V 基本要求:算法合理，结果准确
 终于明白阿里百度这样的大公司，为什么面试经常拿ThreadLocal考验求职者了
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 《奇巧淫技》系列python！！每天早上八点自动发送天气预报邮件到QQ邮箱
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