关于Matrix Script的解法以及正则总结

问题参照：

• https://www.hackerrank.com/challenges/matrix-script/problem

解题思路

• 将N * M矩阵转转化为具有顺序的一维数组
• 将一维数组按照顺序拼接字符串
• 利用正则过滤字符串

code

#!/bin/python3

import math
import os
import random
import re
import sys
if __name__ == '__main__':
    nm = input().split()
    n = int(nm[0])
    m = int(nm[1])
    matrix = []
    for _ in range(n):
        matrix_item = input()
        matrix.append(matrix_item)
    row_column = ["0"]*(n*m)
    row_number = 0
    for index, row in enumerate(matrix):
        for column_index in range(len(row)):
            row_column[column_index*n + index] = row[column_index]
    string = ''
    for i in range(len(row_column)):
        string = string + row_column[i]
    string = "".join('%s' %id for id in row_column)
    string=  (re.sub(r'\b[^a-zA-Z0-9]+\b', ' ', string))
    print(string)

正则表达式浅析

• \b
  \b 匹配一个单词边界，也就是指单词和空格间的位置。例如，「er\b」可以匹配「never」中的「er」，但不能匹配「verb」中的「er」
• '+'
  Causes the resulting RE to match 1 or more repetitions of the preceding RE. ab+ will match ‘a’ followed by any non-zero number of ‘b’s; it will not match just ‘a’.
• '[]'
  里面可以存储一系列(正则)字符

更多参照：https://docs.python.org/3.1/library/re.html