Determine if any 3 integers in an array sum to 0. Note: The following solutions assumes that repetitions (i.e. choosing the same array element more than once) are allowed, so the array [-5,1,10] contains a zero sum (-5-5+10) and so does [0] (0+0+0). [4, 2, -1, 1, -5, 6, -4] = True

solution.js

function detectZero(arr) {
  const map = {};
  for (var i=0; i<arr.length; i++) {
    if (arr[i] === 0) return true;
    if (map[arr[i]]) return true;
    map[arr[i] * -2] = true;
    if (find2Sum(arr.slice(i), -arr[i])) return true;
  }
  return false;
}

function find2Sum(arr, sum) {
  const map = {};
  for (var i=0; i<arr.length; i++) {
    if (map[arr[i]]) return true;
    map[sum - arr[i]] = true;
  }
  return false;
}


const arr1 = [-5,3,1,-8];
console.log(detectZero(arr1));