#include<iostream>
#include<cstring>
#include<string>
using namespace std;
int main() {
	int n;
	char a[100];
	int b=0;
	cin >> n;
	cin.get();//消除换行符
	cin.getline(a, 100);
	int length = strlen(a);
	for (int i = 0; i <= length-1 ; i++) {
		b = a[i] + n;//用ASCII码来运算
		if (b <= 122) {//'z'的ASCII码为122
			cout << char(b);//将ASCII码转化为字符输出
		}
		else {
			for (int j = 1;; j++) {
				b -=26;
				if (b <= 122)break;
			}//for循环用来处理超出z的部分，轮回到a开始
			cout << char(b);//将ASCII码转化为字符输出
		}
	}
}