index.js

/// Problem 1.

function closestNumber(n, m) {
    let i = n-1;
    let j = n+1;
    while(1==1) {
        if(i%m===0 && j%m!==0) {
            return i;
        }
        else if(i%m!==0 && j%m===0) {
            return j;
        }
        else if (i%m===0 && j%m===0) {
            if(i>=0) {
                return j;
            }
            if(j>=-i) {
                return j;
            }
            return i;
        }
        i--;
        j++;
    }
}

// console.log(closestNumber(13, 4));
// console.log(closestNumber(15, 4));


/// Problem 2.

function merge(a, b) {
    let lena = a.length;
    let lenb = b.length;

    let result = "";
    
    let minlen = lena;
    if(lenb < lena) minlen = lenb;

    for(let i=0; i<minlen; i++) {
        result += a[i] + b[i];
    }
    if(lena > lenb) {
        result += a.substr(lenb);
    }
    else if(lena < lenb) {
        result += b.substr(lena);
    }
    return result;
}
// let res = merge("", "asdsa");
// console.log(res);


/// Problem 3.

function remove_duplicate(array, size) { // input: [1,2,2], 3
    let len = array.length;
    let j = 0;

    for(let i=1; i<len; i++) {
        if(array[i] !== array[j]) {
            j++;
            array[j] = array[i];
        }
    }
    array = array.slice(0, j+1);
    return array;
}

// console.log(remove_duplicate([1, 2, 2, 2, 2], 5));
// console.log(remove_duplicate([2, 2, 2, 2, 2], 5));