import java.util.*;

public class rsa {

public static long gcd(long a,long b){

if(a==0) return b;

return gcd(b%a,a);

}

public static long[] keyGenerate(long p,long q){

long n=(p-1)*(q-1);

long e=Integer.MIN_VALUE;

ArrayList<Long> al =new ArrayList<Long>();

for(long key=2;key<=n;key++){

if(gcd(key,n)==1){

al.add(key);

}

}

System.out.println("All possible public key is");

for(int i=0;i<al.size();i++) System.out.println(al.get(i));

e=al.get(0);

long d=Integer.MIN_VALUE;

long index=1;

while (true){

if((index*e)<n){

index++;

}

else{

if((index*e)%n==1){

d=index;

break;

}

index++;

}

}

long[] key=new long[]{e,d};

return key;

}

public static double powerModeFunction(long[] key,double planeText){

double text = Math.pow(planeText,key[0])%key[1];

return text;

}

public static void main(String[] arr){

Scanner sc=new Scanner(System.in);

System.out.println("Enter message ");

double planeText=sc.nextDouble();

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

long p=sc.nextLong();

System.out.println("Enter message q");

long q=sc.nextLong();

long[] keyArray=keyGenerate(p,q);

long[] publicKey=new long[]{keyArray[0],(p)*(q)};

long[] privateKey=new long[]{keyArray[1],(p)*(q)};

double encryptText = powerModeFunction(publicKey,planeText);

System.out.println("Private key is "+privateKey[0]);

System.out.println("Public key is "+publicKey[0]);

System.out.println("Encryption text is "+encryptText);

double decryptText=powerModeFunction(privateKey,encryptText);

System.out.println("Decryption text is "+decryptText);

}

}