#include<bits/stdc++.h>
using namespace std;
int main()
{
	
	int n,i = 0,j = 0;
	char ori[51];
	cin >> n;
	getchar();
	while((ori[i++] = getchar())!= '\n' && i <= 51)	
		ori[i-1] = (ori[i-1] -'a' + n) % 26 + 'a'; 	
	ori[i] = '\0';
	while(ori[j++] != '\0')
		cout << ori[j-1];
		
	return 0;
 }