// ****************************************************************
//   PowersOf2.java
//
//   Print out as many powers of 2 as the user requests
//
// ****************************************************************
import java.util.Scanner;

public class PowersOf2
{
    public static void main(String[] args)
    {
        int numPowersOf2;        //How many powers of 2 to compute
        int nextPowerOf2 = 1;    //Current power of  2
        int exponent=1;            //Exponent for current power of 2 -- this
        //also serves as a counter for the loop
        Scanner scan = new Scanner(System.in);

        System.out.println("How many powers of 2 would you like printed?");
        numPowersOf2 = scan.nextInt();

        //print a message saying how many powers of 2 will be printed
        //initialize exponent -- the first thing printed is 2 to the what?

        while (exponent<=numPowersOf2)
        {
            //print out current power of 2
            nextPowerOf2=nextPowerOf2*2;
            System.out.println("2^"+exponent+" = "+nextPowerOf2);
            exponent++;
        }
    }
}