#!/usr/bin/python3

"""
Translate lists of space separated integers (magnitude less than 62) and print
as strings of alphanumeric characters. This is useful mainly for some machine
learning algorithms that only take string input.

usage: %prog < int_seqs > strings
"""
from __future__ import print_function

import sys

table = "012345678ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"


def main():
    for line in sys.stdin:
        ints = [int(f) for f in line.split()]
        if max(ints) > len(table):
            raise ValueError("Alphabet size too large!")
        print(str.join('', [table[i] for i in ints]))


if __name__ == "__main__":
    main()