NextPowerOf2.java

package com.interview.bits;

/**
 * http://www.geeksforgeeks.org/next-power-of-2/
 */
public class NextPowerOf2 {

    public int nextPowerOf2(int num){
        if(num ==0){
            return 1;
        }
        if(num > 0 && (num & (num-1)) == 0){
            return num;
        }
        while((num & (num-1)) > 0){
            num = num & (num-1);
        }
        return num<<1;
    }
    public static void main(String args[]){
        NextPowerOf2 np = new NextPowerOf2();
        System.out.println(np.nextPowerOf2(4));
    }
}