026_remove_duplicate_from_array.js

const removeDuplicates = function(nums) {
    let len = 0;
    for (let i = 0; i<nums.length; i++) {
        if (nums[i] !== nums[i-1]) {
            nums[len++] = nums[i]
        }
    }
    return len;
};


const nums = [1,1,2];

console.log(removeDuplicates(nums));