Rotate Image

/** Do not return anything, modify matrix in-place instead. */
export function rotate(matrix: number[][]): void {
  const [m, n] = [matrix.length, matrix[0].length];
 
  for (let i = 0; i < m; i++) {
    for (let j = i + 1; j < n; j++) {
      [matrix[i][j], matrix[j][i]] = [matrix[j][i], matrix[i][j]];
    }
  }
 
  for (let i = 0; i < m; i++) {
    matrix[i].reverse();
  }
}