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// Find all possible sums made from subsets of items from array A

function subsetSums(arr, l, r, sum = 0) {
  // Print current subset
  if (l > r) {
    console.log(sum);
    return;
  }

  // Subset including arr[l]
  subsetSums(arr, l + 1, r, sum + arr[l]);

  // Subset excluding arr[l]
  subsetSums(arr, l + 1, r, sum);
}

let arr = [5, 4, 3, 1]; 
subsetSums(arr, 0, arr.length - 1); // 2^n results