Function checkSubarraySum

javascript/0523-continuous-subarray-sum.js:9–24

(arr, k)

 * @return {boolean}
 */
var checkSubarraySum = function (arr, k) {
    let sum = 0;
    const remainderMap = new Map([[0, -1]]);

    for (let i = 0; i < arr.length; i++) {
        sum += arr[i];
        if (remainderMap.has(sum % k) && i - remainderMap.get(sum % k) > 1) {
            return true;
        }
        if (!remainderMap.has(sum % k)) {
            remainderMap.set(sum % k, i);
        }
    }

    return false;
};