dg

 package excel;

 import java.util.Scanner;

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

         System.out.println(f(2,4));

     }

     static int f(int a,int n){
         if(n>1){
             return pf(f(a,n/2));

         }else{
             return a;

         }
     }

     static int pf(int a){
     return a*a;
     }

 }