#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <algorithm>
#include <string>
#include <functional>
#include <vector>
#include <deque>
#include <utility>
#include <bitset>
#include <limits.h>
#include <time.h>
using namespace std;
typedef long long ll;
typedef unsigned long long llu;
typedef double lf;
typedef unsigned int uint;
typedef long double llf;
typedef pair<int, int> pii;
int n;
char str[1000];
int main() {
scanf("%d", &n);
while(~scanf("%s", str)) {
for(int x = 0; str[x] && str[x+1]; x += 2) {
putchar( ((str[x]-'a') + (str[x+1]-'a') - n + 26) % 26 + 'a' );
}
putchar(32);
}
return 0;
}
