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Find all groups of three values from an array that add up to the given value

Find all groups of three values from an array that add up to the given value

const threeSum = (arr, sum) => {
  const ans = [];
  const ilength = arr.length-2;
  const jlength = ilength+1;
  let check = false;
  for(let i=0, j=i+1, k=j+1; i<ilength; i++, j++, k++) {
    if (arr[i]+arr[j]+arr[k] === sum) {
      ans.push([arr[i], arr[j], arr[k]]);
    }
    if (j<jlength) {
      i--;
    } else {
      j=i+1;
    }
    if (k<arr.length) {
      j--;
    } else {
      k=j+1;
    }
  }
  return ans;
}

Test Input

console.log(threeSum([-1, 0, 1, 2, -1, -4, -3, 5, -6, 0], 4))

Output

[ [ -1, 0, 5 ],
  [ -1, 5, 0 ],
  [ 0, -1, 5 ],
  [ 2, -3, 5 ],
  [ -1, 5, 0 ] ]
Run the code here: https://repl.it/@VinitKhandelwal/15-leetcode-3sum


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