package test;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
// 非负整数 小于10000
// 2+3*4-2+5+3*2-100
String line;
String right;
String left;
String middle;
String sign1;
String sign2;
line = in.nextLine();
int lineLength = line.length();
if (lineLength > 0) {
do {
// 获取最右边的加减号
int addIndex = line.lastIndexOf("+");
int subIndex = line.lastIndexOf("-");
int mulIndex = line.lastIndexOf("*");
int divIndex = line.lastIndexOf("/");
// 加减乘除 不存在,
// 或者只有最前面的负号, 则终止循环, 输出结果
if (addIndex == -1 && mulIndex == -1 && divIndex == -1) { // end start
if (subIndex == -1) {
break;
} else if (subIndex != -1) {
int subSecondIndex = line.lastIndexOf("-", subIndex - 1);
if (subIndex == 0 && subSecondIndex == -1) {
break;
}
}
} // end end
if (addIndex == -1 && subIndex == -1) { // 加减 无
if (divIndex == -1 && mulIndex == -1) { // 加减 乘除 无
System.out.println(line);
} else { // 乘除 只有
line = getMulDivResult(line);
}
} else { // 加减 有
// 以最右边的加减号为断点, 开始截取字符串
int asIndex = getMaxIndex(addIndex, subIndex);
if (divIndex == -1 && mulIndex == -1) { // 加减 只有
line = getAddSubResult(line);
} else { // 加减乘除 都有
// 从最后一个加减号截取来的字符串
String str2 = line.substring(asIndex + 1);
middle = String.valueOf(line.charAt(asIndex));
left = line.substring(0, asIndex);
int mdIndex = getMaxIndex(mulIndex, divIndex);
right = str2;
if (mdIndex > asIndex) { // 在最后一个加减号的后面还存在乘除
right = getMulDivResult(str2);
line = left + middle + right;
} else if (mdIndex < asIndex) { // 在最后一个加减号的后面, 只是单个数字
// 查找最后一个加减号之前, 即紧挨着的加减号, 截取其中的乘除字符串
int add2Index = line.lastIndexOf("+", asIndex - 1);
int sub2Index = line.lastIndexOf("-", asIndex - 1);
// 在最后一个加减号, 左边全是乘除, 右边随意
if (add2Index == -1 && sub2Index == -1) {
left = line.substring(0, asIndex);
left = getMulDivResult(left);
right = line.substring(asIndex + 1);
middle = String.valueOf(line.charAt(asIndex));
line = left + middle + right;
} else { // 有加减 有乘除
int leftIndex = getMaxIndex(line.lastIndexOf("+", mdIndex - 1),
line.lastIndexOf("-", mdIndex - 1));
int rightIndex = getMinIndex(line.indexOf("+", mdIndex + 1),
line.indexOf("-", mdIndex + 1));
if (leftIndex != -1) {
sign1 = String.valueOf(line.charAt(leftIndex));
left = line.substring(0, leftIndex);
} else {
sign1 = "";
left = "";
}
if (rightIndex != -1) {
sign2 = String.valueOf(line.charAt(rightIndex));
} else {
sign2 = "";
}
middle = line.substring(leftIndex + 1, rightIndex);
middle = getMulDivResult(middle);
right = line.substring(rightIndex + 1);
line = left + sign1 + middle + sign2 + right;
}
}
}
}
} while (line.indexOf("+") != -1 || line.indexOf("-") != -1 || line.indexOf("*") != -1
|| line.indexOf("/") != -1);
System.out.println(line);
} // end if
in.close();
// 提示：一种可能的做法是，将整个式子作为字符串读入，
// 然后找出其中最后一个+或-，在此位置将其截成两段，
// 分别计算后再做+或-，以此类推。
// 另，用Integer.parseInt(s)可以从一个字符串得到整数。
}
/**
* 单纯乘除计算
*
* @param line
* @return
*/
public static String getMulDivResult(String line) {
String retStr = null;
String leftStr = null;
String endStr = null;
do {
if (endStr != null) {
line = leftStr + endStr;
}
int index = getMinIndex(line.indexOf("*"), line.indexOf("/"));
String sign = String.valueOf(line.charAt(index));
leftStr = line.substring(0, index);
int index2 = getMinIndex(line.indexOf("*", index + 1), line.indexOf("/", index + 1));
String rightStr = null;
if (index2 != -1) {
rightStr = line.substring(index + 1, index2);
endStr = line.substring(index2);
} else if (index2 == -1) {
rightStr = line.substring(index + 1);
endStr = line.substring(index + rightStr.length() + 1);
}
switch (sign) {
case "*":
leftStr = String.valueOf(Integer.parseInt(leftStr) * Integer.parseInt(rightStr));
break;
case "/":
leftStr = String.valueOf(Integer.parseInt(leftStr) / Integer.parseInt(rightStr));
break;
}
retStr = leftStr + endStr;
} while (endStr.length() > 1);
return retStr;
}
/**
* 单纯加减计算
*
* @param line
* 10-4+5
* @return
*/
public static String getAddSubResult(String line) {
String retStr = null;
String leftStr = null;
String endStr = null;
do {
if (endStr != null) {
line = leftStr + endStr;
}
int index = getMinIndex(line.indexOf("+"), line.indexOf("-"));
if (index == 0) {
index = getMinIndex(line.indexOf("+", index + 1), line.indexOf("-", index + 1));
}
String sign = String.valueOf(line.charAt(index));
leftStr = line.substring(0, index);
int index2 = getMinIndex(line.indexOf("+", index + 1), line.indexOf("-", index + 1));
String rightStr = null;
if (index2 != -1) {
rightStr = line.substring(index + 1, index2);
endStr = line.substring(index2);
} else if (index2 == -1) {
rightStr = line.substring(index + 1);
endStr = line.substring(index + rightStr.length() + 1);
}
switch (sign) {
case "+":
leftStr = String.valueOf(Integer.parseInt(leftStr) + Integer.parseInt(rightStr));
break;
case "-":
leftStr = String.valueOf(Integer.parseInt(leftStr) - Integer.parseInt(rightStr));
break;
}
retStr = leftStr + endStr;
} while (endStr.length() > 1);
return retStr;
}
/**
* 获取非-1, 较大数字的下标
*
* @param index1
* @param index2
* @return
*/
public static int getMaxIndex(int index1, int index2) {
int max = -1; // 提前假设两者都是-1
if (index1 > index2) {
max = index1;
}
if (index1 < index2) {
max = index2;
}
return max;
}
/**
* 获取非-1, 较小数字的下标
*
* @param index1
* @param index2
* @return
*/
public static int getMinIndex(int index1, int index2) {
int ret = 1;
if (index1 == -1) {
ret = index2;
} else if (index2 == -1) {
ret = index1;
} else if (index1 > index2) {
ret = index2;
} else if (index1 < index2) {
ret = index1;
}
return ret;
}
}
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