#include <bits/stdc++.h>
using namespace std;
string s;
int n;
int main()
{
	cin>>n;
	getline(cin,s);
	//string a=s+s+s;
	int l=s.size();
	for(int i=i+1;i<l+l;i++){
		if(s[i]!='z')  s[i]=s[i]+n;
		else s[i]=s[i]-26+n;
		cout<<s[i];
		
	}
	return 0;
 }