#!/usr/bin/env python

import re
import sys

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

if __name__ == "__main__":
    main()