SubsetBit

package com.gokul.demo.Success;

import java.util.ArrayList;
import java.util.List;

public class SubsetBit {
    public static void main(String[] args) {

        SubsetBit sub = new SubsetBit();
        int[] arr = new int[] { 1, 2, 3, 4 };
        sub.subsets(arr);
    }

    List<List<Integer>> opList = new ArrayList<>();

    public List<List<Integer>> subsets(int[] nums) {
        for (int i = 0; i < Math.pow(2, nums.length); i++) {

            opList.add(getBinary(i, nums.length, nums));

        }
        return opList;
    }

    private List<Integer> getBinary(int num, int size, int[] nums) {
        List<Integer> minList = new ArrayList<>();
        String binaryString = Integer.toBinaryString(num);

        while (binaryString.length() < size) {
            binaryString = "0" + binaryString;
        }
        char[] charArray = binaryString.toCharArray();
        for (int i = 0; i < charArray.length; i++) {
            if ('1' == charArray[i]) {
                minList.add(nums[i]);
            }
        }
        return minList;
    }

}