#include<bits/stdc++.h>

using namespace std;

int gcdExtended(int a, int b, int* x, int* y)
{

    if (a == 0)
    {
        *x = 0, *y = 1;
        return b;
    }

    int x1, y1;
    int gcd = gcdExtended(b % a, a, &x1;, &y1;);


    *x = y1 - (b / a) * x1;
    *y = x1;

    return gcd;
}



int modInverse(int A, int M)
{
    int x, y;
    int g = gcdExtended(A, M, &x, &y);
    if (g != 1)
        return -1;
    else
    {
        int res = (x % M + M) % M;
        return res;
    }
}

void decryption(string s,int ky1,int ky2)
{

    string decrp="";
    //cout<<"\n\n Enter cipher text : ";
    //cin.ignore();
    //getline(cin,s);
    //int ky1,ky2;
    //cout<<"Enter the first key : ";
   // cin>>ky1;
    //cout<<"Enter the second key : ";
   // cin>>ky2;
    int res=modInverse(ky1,26);
    if(res==-1)
    {
        cout<<"Modular inverse of key 1 does not exist!!";
        return;
    }
    char ar[]= {'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};

    for(int i=0; i<<"\n\n The decrypted message for the given text : "<<decrp<<endl;
}

int main()
{
    string s,encrp="";
    cout<<"Enter plain text : ";
    getline(cin,s);
    int ky1,ky2;
    cout<<"Enter the first key : ";
    cin>>ky1;
    cout<<"Enter the second key : ";
    cin>>ky2;
    char ar[]= {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};

    int i=s[0]-'a';

    for(int i=0; i<<"\nThe encryption for the given ciphertext: "<<encrp<<endl;

    decryption(encrp,ky1,ky2);

}