Remove Element

removeElement.ts

/*
 * https://leetcode.com/problems/remove-element/description/?envType=study-plan-v2&id=top-interview-150
 */
function removeElement(nums: number[], val: number): number {
    /*
        I1: nums = [l(k(3)), 2, 2, 3], val = 3
        I2: nums = [l(2), k(2), 2, 3], val = 3
        I3: nums = [2, l(2), k(2), 3], val = 3
        I4: nums = [2, 2, l(3), k(3)], val = 3
    */

    let l = 0, k = 0;

    while (k < nums.length) {
        nums[l] = nums[k];

        if (nums[l] !== val) {
            l++
        }

        k++;
    }

    return l;
};

removeElemtsWithFor.ts

function removeElement(nums: number[], val: number): number {
    /*
        I1: nums = [l(k(3)), 2, 2, 3], val = 3
        I2: nums = [l(2), k(2), 2, 3], val = 3
        I3: nums = [2, l(2), k(2), 3], val = 3
        I4: nums = [2, 2, l(3), k(3)], val = 3
    */

    let l = 0;

    for (let k = 0; k < nums.length; k++) {
        nums[l] = nums[k];

        if (nums[l] !== val) {
            l++
        }
    }

    return l;
};