【leetcode】867 - Transpose Matrix

【题干描述】

Given a matrix A, return the transpose of A.

The transpose of a matrix is the matrix flipped over it's main diagonal, switching the row and column indices of the matrix.(一矩阵A，返回其转置)

【思路】

• 直接处理，A[i][j]的值赋值给output[j][i].

【python代码】

 input = [[1, 2, 3], [4, 5, 6]]
     row = len(input)
     col = len(input[0])

     output = [[None]*row for _ in range(col)]

     for j in range(col):
         for i in range(row):
             output[j][i] = input[i][j]
     print output

【所用python点】

• range()和xrange()的区别：https://www.cnblogs.com/Sinkinghost/p/9320070.html
• [[None]*row for _ in range(col)] 的 “_” 其实可以用 任意变量替换。
• [None]*row 的结果是[None, None, None]