"use strict";
    
const main = arg => {
    arg = arg.trim().split("\n");
    const N = parseInt(arg[0]);
    const S = arg[1].split("");
    
    const alpha = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"];
    
    let answer = [];
    
    for(let i in S) {
        let temp = alpha.indexOf(S[i]);
        
        if(temp + N >= 26) {
            temp = temp - 26;
        }
        
        answer.push(alpha[temp + N]);
    }
    
    console.log(answer.join(""))
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));