#!/usr/bin/env python3
#
#
# Copyright (c) 2021, Hiroyuki Ohsaki.
# All rights reserved.
#
# $Id: count.py,v 1.2 2021/11/15 10:35:18 ohsaki Exp $
#

import sys

def usage():
    print(f"usage: {sys.argv[0]} string", file=sys.stderr)
    exit(1)

def main():
    # Extract the first argument.
    if len(sys.argv) <= 1:
        usage()
    astr = sys.argv[1]

    # Count the number of occurences.
    counts = {}
    for c in astr:
        # Dictionary element must be explicitly initialized.  Otherwise, you can 
        # use collections.defaultdict class. 
        if c not in counts:
            counts[c] = 0
        counts[c] += 1

    # Display counts for every character.
    for c, n in counts.items():
        print(c, n)

if __name__ == "__main__":
    main()