#include <stdio.h>
#define DuRu_n int n=0;scanf("%d",&n);

int main(){
	DuRu_n;
	
	n%=26;
	getchar();
	char ch=getchar();
	
	while(ch>='a'&&ch<='z'){
		if(ch+n<='z'){
			putchar(ch+n);
		}else{
			putchar(ch+n-26);
		}
		ch=getchar();
	}
	
	return 0; 
}