#!/usr/bin/env python

import re, sys

def main():
    with open("text.in", "r+") as file_in:
        words = re.findall(r"[a-zA-Z]+", file_in.read())
        if len(words) == 0:
            sys.exit(0)
        with open("text.out", "r+") as file_out:
            average = len(''.join(words)) // len(words)
            file_out.write("{}\n".format(average))

if __name__ == "__main__":
    main()