0189-rotate-array.ts

/**
 Do not return anything, modify nums in-place instead.
 */
function rotate(nums: number[], k: number): void {
    k = k % nums.length;
    let l = 0;
    let r = nums.length - 1;
    while (l < r) {
        let temp = nums[l];
        nums[l] = nums[r];
        nums[r] = temp;
        l += 1;
        r -= 1;
    }

    l = 0;
    r = k - 1;
    while (l < r) {
        let temp = nums[l];
        nums[l] = nums[r];
        nums[r] = temp;
        l += 1;
        r -= 1;
    }

    l = k;
    r = nums.length - 1;
    while (l < r) {
        let temp = nums[l];
        nums[l] = nums[r];
        nums[r] = temp;
        l += 1;
        r -= 1;
    }
}