48-Rotate-Image.ts

function rotate(matrix: number[][]): void {
    let l = 0;
    let r = matrix.length - 1;

    while (l < r) {
        for (let i = 0; i < r - l; i++) {
            let top = l;
            let bottom = r;

            let topLeft = matrix[top][l + i];

            matrix[top][l + i] = matrix[bottom - i][l];
            matrix[bottom - i][l] = matrix[bottom][r - i];
            matrix[bottom][r - i] = matrix[top + i][r];
            matrix[top + i][r] = topLeft;
        }
        r -= 1;
        l += 1;
    }
}