JS SubsetSum

JS-SubsetSum.js

// Will actually work without the 'String()` whatnot, but I'm being particular

const subsetSum = (arr, target) => {
  let dictObj = {}; 
  for (let i = 0; i < arr.length; i++) {
    const val = arr[i]; 
    const compliment = String(target - val);

    if (dictObj.hasOwnProperty(compliment)) { // must use hasOwnProp in case of index=0 which would return as false!!
      return [dictObj[compliment],i];
    }
    
    dictObj[String(val)] = i;
  }
  return false;
};
console.log(subsetSum([2, 7, 11, 6], 9)); // [0,1]

Sacrifices O(n^2) to become 0(n), but adds the space complexity of O(n) which doesn't happen in an embedded-loop version.