Sum of duplicate array

by Nidhi Patel

JavaScript

function removeDuplicate(n) {
  let arr = [];
  let arr1 = [];
  for (var i = 0; i < n.length; i++) {
    if (arr.indexOf(n[i]) === -1) {
      arr.push(n[i])
    } else {
      arr1.push(n[i]);
    }
  }
  return sum(arr1);
}

function sum(n) {
  var sum = 0;
  for (i in n) {
    sum += n[i];
  }
  return sum;
}

console.log(removeDuplicate([1, 8, 3, 6, 9, 4, 3, 8]));