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. 1 <= A.length <= 1000
2. 1 <= A[0].length <= 1000

Solution: Brute Force

Time complexity: O(mn)

Space complexity: O(mn)

// Author: Huahua
// Running time: 16 ms
class Solution {
public:
  vector<vector<int>> transpose(vector<vector<int>>& A) {
    int m = A.size();
    int n = A[0].size();
    vector<vector<int>> ans(n, vector<int>(m));
    for (int i = 0; i < m; ++i)
      for (int j = 0; j < n; ++j)
        ans[j][i] = A[i][j];
    return ans;
  }
};

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