#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <stdlib.h>
#include <time.h>
#include <ctype.h>
using namespace std;


int                              n;
int                      l =     0;
bool                   ans = false;

int                 GetRandomnum();




/////////////////////////////////////////////////////////////////////
int main()                                                         //
{

    srand(time(0) );

    cin >> n;
    char *sz2 = new char[n];
    cout <<"enter messages" << endl;

    cin >> sz2;

    char ABC[49] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ_.,0123456789";
    char abc[] = { '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','_','.',',','0',
            '1','2','3','4','5','6','7','8','9' };


    for(int j = 0; j < n; j++)
    {
            ans = isupper(sz2[j]);

            if(ans == true)
            {
                sz2[j] = ABC[GetRandomnum() + j];
            }
            else
            {
                sz2[j] = abc[GetRandomnum() + j];
            }
    }


    cout << sz2;
}



///////////////////////////////////////////////////////////////////////
int GetRandomnum()                                                   //
{



    int num = rand()%26 + 1;

return num;
}