#include <bits/stdc++.h>
using namespace std;
int main() {
int n;
scanf("%d",&n);
n %= 26;
while (1) {
string s;
getline(cin, s);
if (s == "over") return 0;
int l=s.size();
for (int i = 0; i < l; ++i) {
if (s[i] >= 'a' && s[i] <= 'z') {
char tar = s[i] - n;
if (tar < 'a') printf("%c",char('z'-'a'+tar+1));
else printf("%c",tar);
} else if (s[i] >= 'A' && s[i] <= 'Z') {
char tar = s[i] - n;
if (tar < 'A') printf("%c",char('Z'-'A'+tar+1));
else printf("%c",tar);
}
else cout << s[i];
}
printf("\n");
}
return 0;
}
