how to get distinct combinations of a set in javascript

index.tsx
function getCombinations(set) {
  let memo = {}; // memoization object to store already computed combinations
  function helper(set) {
    let key = set.toString(); // convert set to string for memoization
    if (memo.hasOwnProperty(key)) return memo[key]; // if already computed, return from memo
    let result = [];
    if (set.length == 0) {
      result.push([]); // base case
      return result;
    }
    let first = set[0];
    let rest = set.slice(1);
    let subCombs = helper(rest);
    result = result.concat(subCombs);
    subCombs.forEach(function(subComb) {
      let comb = [first].concat(subComb);
      result.push(comb);
    });
    memo[key] = result; // memoize the result
    return result;
  }
  return helper(set);
}

// Example usage:
let set = [1, 2, 3];
let combs = getCombinations(set);
console.log(combs);
// Output: [[], [3], [2], [2, 3], [1], [1, 3], [1, 2], [1, 2, 3]]
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