A_AB_Balance.cpp

#include <bits/stdc++.h>
#include <algorithm>
#include <set>
#include <math.h>
#include <vector>
#define int long long 
using namespace std;
int gcd(int a, int h){
    int temp;
    while (1){
        temp = a%h;
        if (temp == 0)
            return h;
        a = h;
        h = temp;
    }
}

int32_t main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    double p = 3;
    double q = 7;
    double n = p*q;
    double e = 2;
    double phi = (p-1)*(q-1);
    while (e < phi){
        if (gcd(e, phi)==1)
            break;
        else
            e++;
    }
    int k = 2;
    double d = (1 + (k*phi))/e;
    double msg = 12;
    cout <<"Message data = "<< msg;
    double c = pow(msg, e);
    c = fmod(c, n);
    cout << "\nEncrypted data = " << c;
    double m = pow(c, d);
    m = fmod(m, n);
    cout << "\nOriginal Message Sent = " << m;
    return 0;
}