// Split items into `groupCount` round-robin buckets.

function partition<T>(items: T[], groupCount: number): T[][] {

  const buckets: T[][] = Array(groupCount).fill([]);

  items.forEach((item, i) => {

    buckets[i % groupCount].push(item);

  });

  return buckets;

}

const result = partition(["a", "b", "c", "d"], 2);

console.log(result[0]); // expected: ["a", "c"]

console.log(result[1]); // expected: ["b", "d"]