编程介的小学生 2017-01-07 16:15 采纳率: 20.5%
浏览 765
已采纳

PreQueL

Description

In some simplistic DBMS named PreQueL, the only column type allowed is CHAR(1) (a single character), and furthermore, its values are restricted to English upper-case letters ('A' to 'Z'). Table may contain up to 9 columns, numbered from 1 to 9. Tables themselves are named with lower-case English letters ('a' to 'z').

The only database query possible first joins all the tables, then selects some rows according to conditions in one of two forms: either < column>=< value> or < column1>=< column2>, for example a2=A or b1=c4. All conditions must hold simultaneously, as if they were connected by 'AND' operator.

You must write a PreQueL processor, which, given a tables and a set of conditions, will produce query result, i.e. those rows of a join satisfying all the conditions. Resulting rows must be sorted alphabetically.
Input

The first line of input file contains of two integers - number of tables T and number of conditions D.

Starting from the second line there are T tables represented with number of rows RN and number of columns CN in the first line of a table, which is followed by RN lines consisting of exactly CN characters each. D lines with conditions follow the whole set of tables.

The constraints are: 1 <= T <= 26, 1 <= D <= 50, 1 <= CN <= 9, 1 <= RN <= 1000.
Output

Output file contains result rows, one row per line. No input query will produce more than 1000 rows. The result rows are to be sorted alphabetically.
Sample Input

2 2
3 2
AX
BX
BY
2 3
ACD
BCC
a1=b1
a2=X
Sample Output

AXACD
BXBCC

  • 写回答

1条回答

  • threenewbee 2017-01-07 16:16
    关注
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

报告相同问题?

悬赏问题

  • ¥15 基于卷积神经网络的声纹识别
  • ¥15 Python中的request,如何使用ssr节点,通过代理requests网页。本人在泰国,需要用大陆ip才能玩网页游戏,合法合规。
  • ¥100 为什么这个恒流源电路不能恒流?
  • ¥15 有偿求跨组件数据流路径图
  • ¥15 写一个方法checkPerson,入参实体类Person,出参布尔值
  • ¥15 我想咨询一下路面纹理三维点云数据处理的一些问题,上传的坐标文件里是怎么对无序点进行编号的,以及xy坐标在处理的时候是进行整体模型分片处理的吗
  • ¥15 CSAPPattacklab
  • ¥15 一直显示正在等待HID—ISP
  • ¥15 Python turtle 画图
  • ¥15 stm32开发clion时遇到的编译问题