import java.util.*;

public class Diffie_Hellman

{

public static void main(String args[])

{

Scanner sc=new Scanner(System.in);

System.out.println("Enter modulo(p)");

int p=sc.nextInt();

System.out.println("Enter primitive root of "+p);

int g=sc.nextInt();

System.out.println("Choose 1st secret no(DEEPANSHU)");

int a=sc.nextInt();

System.out.println("Choose 2nd secret no(GOYAL)");

int b=sc.nextInt();

int A = (int)Math.pow(g,a)%p;

int B = (int)Math.pow(g,b)%p;

int S_A = (int)Math.pow(B,a)%p;

int S_B =(int)Math.pow(A,b)%p;

if(S_A==S_B)

{

System.out.println("DEEPANSHU and GOYAL can communicate with each other....");

System.out.println("They share a secret no = "+S_A);

}

else

{

System.out.println("DEEPANSHU and GOYAL cannot communicate with each other....");

}

}

}