566. Reshape the Matrix

class Solution(object):    def matrixReshape(self, nums, r, c):        """        :type nums: List[List[int]]        :type r: int        :type c: int        :rtype: List[List[int]]        """        res=[[None]*c for i in range(r)]        if len(nums)*len(nums[0]) != r*c:            return nums        else:            for i in range(len(nums)*len(nums[0])):                res[i/c][i%c] = nums[i/len(nums[0])][i%len(nums[0])]        return res

• 关于二维列表的初始化res=[[None]*c for i in range(r)],c是列数，i是行数，这里的i无实际意义，res=[[None]*c for _ in range(r)]