PowerSet.java

/* *****************************************************************************
 *  Name:              Jaya Mukherjee
 *  Coursera User ID:  xxxx
 *  Last modified:     October 8, 2021
 **************************************************************************** */

public class PowerSet {


    static void printPowerSet(char[] set,
                              int set_size) {

        /* set_size of power set of a set
        with set_size n is (2**n -1) */
        long pow_set_size =
                (long) Math.pow(2, set_size);
        int counter, j;

        // Run from counter 000..0 to  111..1
        for (counter = 0; counter <
                pow_set_size; counter++) {
            for (j = 0; j < set_size; j++) {
                /* Check if jth bit in the
                counter is set If set then
                print jth element from set */
                if ((counter & (1 << j)) > 0)
                    System.out.print(set[j]);
            }

            System.out.println();
        }
    }

    public static void main(String[] args) {
        char[] set = { 'a', 'b', 'c' };
        printPowerSet(set, 3);
    }
}