function convert(data) {
  return (data)
    .toString(26)
    .toUpperCase()
    .split("")
    .map(function (s, i) {
      var code = s.charCodeAt(0)
      return (code <= 57)
        ? code + 7 + 10
        : code + 10
    })
    .map(function (code, i, array) {
      var offset = (array.length - 1 == i)
        ? 0
        : -1
      return String.fromCharCode(code + offset)
    })
}
function Main(input) {
    var input = input.toString().split('\n')[0];
    var N=parseInt(input)
    console.log(convert(N))
}

// Don't edit this line!
Main(require("fs").readFileSync("/dev/stdin", "utf8"));