subsets.go

package main

import (
	"fmt"
	"math"
	"strconv"
)

func formatZeros(binary string, total int) string {

	temp := binary
	for i := 0; i < total-len(binary); i++ {
		temp = "0" + temp
	}

	return temp
}

func toBinary(n int) string {
	return strconv.FormatInt(int64(n), 2)
}

func subsets(set []int) [][]int {

	setSize := len(set)
	var sets [][]int

	for i := 0; i < int(math.Pow(2, float64(setSize))); i++ {

		var subset []int

		for index, c := range formatZeros(toBinary(i), setSize) {
			if string(c) == "1" {
				subset = append(subset, set[index])
			}
		}

		sets = append(sets, subset)
	}

	return sets
}

func main() {

	set := []int{
		1,
		2,
		3,
		4,
		5,
	}

	all := subsets(set)

	fmt.Printf("%v \n", all)

}