Java

lizncu

class Solution {
  public int[][] transpose(int[][] A) {
    if (A.length == A[0].length) {
      for (int i = 1; i < A.length; i++) {
        for (int j = 0; j < i; j++) {
          int temp = A[i][j];
          A[i][j] = A[j][i];
          A[j][i] = temp;
        }
      }

      return A;
    }

    else {
      int[][] B = new int[A[0].length][A.length];
      for (int i = 0; i < A[0].length; i++) {
        for (int j = 0; j < A.length; j++) {
          B[i][j] = A[j][i];
        }
      }
      return B;
    }
  }
}