867. Transpose Matrix

Given a 2D integer array matrix, return the transpose of matrix.

The transpose of a matrix is the matrix flipped over its main diagonal, switching the matrix's row and column indices. link: https://leetcode.com/problems/transpose-matrix/

Example

Example 1:

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

Example 2:

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

/**
 * @param {number[][]} matrix
 * @return {number[][]}
 */
var transpose = function (matrix) {
  if (!matrix.length) return;
  const numOfCols = matrix[0].length;
  const numOfRows = matrix.length;
  const result = [];
  for (let i = 0; i < numOfCols; i++) {
    result.push([]);
  }
  for (let i = 0; i < numOfCols; i++) {
    for (let j = 0; j < numOfRows; j++) {
      result[i][j] = matrix[j][i];
    }
  }
  return result;
};