1. [顺时针打印二维数组] 输入一个矩阵，按照从外向里以顺时针的顺序依次打印出每一个数字，例如，如果输入如下4 X 4矩阵： 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 则依次打印出数字1,2,3,4,8,12,16,15,14,13,9,5,6,7,11,10.
1 def output_array(matrix): 2 ''' 3 输入一个矩阵，返回一个顺时针打印的列表 4 :param matrix: 矩阵（二维数组） 5 :return: list 6 ''' 7 list = [] 8 while True: 9 try: 10 # 顺序打印矩阵第一行 11 len_top = len(matrix[0]) 12 for i in range(len_top): 13 list.append(matrix[0].pop(0)) 14 matrix.pop(0) # ①第一行的元素已经pop完了，但是此时matrix[0] = []而非none，所以这里得pop一下 15 16 # 依次打印最右边的一列（每一行的最后一个元素） 17 len_right = len(matrix) 18 for j in range(len_right): 19 list.append(matrix[j].pop(-1)) 20 21 # 倒序打印最下面一行 22 len_bottom = len(matrix[0]) 23 for k in range(len_bottom): 24 list.append(matrix[-1].pop(-1)) 25 matrix.pop(-1) # 同① 26 27 # 倒序打印最左边的一行（倒序打印每一行的第一个元素） 28 len_left = len(matrix) 29 for l in range(len_left): 30 list.append(matrix[-l-1].pop(0)) 31 32 except BaseException: # 这是个比较懒的方法，没有设置跳出条件，只有触发list out of range 来跳出循环 33 return list 34 35 # --------测试用例------------------ 36 if __name__ == '__main__': 37 a = [[1,2,3],[4,5,6],[7,8,9],[10,11,12],[13,14,15],[16,17,18]] # 小奇数*大偶数 38 b = [[1,2,3,4,5,6],[7,8,9,10,11,12],[13,14,15,16,17,18]] # 大奇数*小偶数 39 c = [[1,2,3,4],[5,6,7,8],[9,10,11,12],[13,14,15,16]] # 偶数*偶数 40 d = [[1,2,3],[4,5,6],[7,8,9]] # 奇数*奇数 41 e = [[1,2],[3,4],[5,6]] # 小偶数*大奇数 42 f = [[1,2,3,4]] # 大偶数*小奇数 43 for i in [a,b,c,d,e,f]: 44 print(output_array(i))
输出：
1 /Users/***/anaconda3/bin/python /Users/***/Documents/project/0911/面试/牛客编程/顺时针打印矩阵.py 2 [1, 2, 3, 6, 9, 12, 15, 18, 17, 16, 13, 10, 7, 4, 5, 8, 11, 14] 3 [1, 2, 3, 4, 5, 6, 12, 18, 17, 16, 15, 14, 13, 7, 8, 9, 10, 11] 4 [1, 2, 3, 4, 8, 12, 16, 15, 14, 13, 9, 5, 6, 7, 11, 10] 5 [1, 2, 3, 6, 9, 8, 7, 4, 5] 6 [1, 2, 4, 6, 5, 3] 7 [1, 2, 3, 4] 9 Process finished with exit code 0
2. [快速排序] 输入一个无序列表，然后返回从小到大排序的列表
1 #-*- coding:utf-8 -*- 2 #Author: Bing Xu 3 4 def quick_sort(list,start,end): 5 6 if start >= end: 7 return list 8 9 low = start 10 high = end 11 mid = list[start] 12 13 while low < high: 14 while low < high and list[high] >= mid: 15 high -= 1 16 list[low] = list[high] 17 while low < high and list[low] < mid: 18 low += 1 19 list[high] = list[low] 20 list[low] = mid 21 quick_sort(list,start,low-1) 22 quick_sort(list,low+1,end) 23 return list 24 25 #------------- 测试 --------------- 26 if __name__ == '__main__': 27 a = [1,2,6,5,3] 28 b = [] 29 # c = [-1,1,3,'l'] 30 # e = [1+2j,1,2] 暂不支持比较字符和复数，明天再想办法解决 31 for i in [a,b]: 32 print(quick_sort(i,0,len(i)-1))
输出：
1 [1, 2, 3, 5, 6] 2 [] 3 4 Process finished with exit code 0