Problem

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.

Example 1:

Input: [[1,2,3],[4,5,6],[7,8,9]] Output: [[1,4,7],[2,5,8],[3,6,9]]

Example 2:

Input: [[1,2,3],[4,5,6]] Output: [[1,4],[2,5],[3,6]]

Note:

1 <= A.length <= 1000 1 <= A[0].length <= 1000

Pre analysis

Will make new matrix with B[col][row] = A[row][col]

Time Complexity = O(M x N) Space Complexity = O(M x N)

Another solution

//Looking for in place restore!