const input = require('fs').readFileSync('/dev/stdin', 'utf8').split('\n');

function main(input) {
  const num = Number(input[0]);
  var str = input[1].split('');
  
  for(var i = 0;i < str.length ;i++){
    var afterInc = str[i].charCodeAt(0) + num;
    if(afterInc > 90){
      afterInc -= 26;
    }
    str[i] = String.fromCharCode(afterInc);
  }
  console.log(str.join(''));
};

main(input);


