GFG A number is a power of 2 or not.

 package com.company;

public class CWR_PowerOfTwo {
// By using brian kerningam's method
    public static boolean check1(int n){
       if(n==0){
           return false;
       }
       return (n&(n-1))==0;
    }
    //        My method T.C ---> O(n) in worst case
    public static String check(int n) {
        for (int i = 0; i < n; i++) {
            if (n == Math.pow(2, i)) {
                return "yes";
            }
        }
        return "No";
    }
    public static void main(String[] args) {
        System.out.println(check1(204));
    }
}