reducer.py

#!/usr/bin/python
# -*- coding: utf-8 -*-

__author__ = 'Takahiro Ikeuchi'

import sys
import re
from collections import defaultdict


def main():

    line = sys.stdin.readline()
    sum_dict = defaultdict(int)

    try:
        while line:
            key, value = line.split('\t')
            value = re.sub('\n', '', value)

            sum_dict[key] += int(value)

            line = sys.stdin.readline()

        for key, value in sum_dict.items():
            print key + '\t' + str(value)

    except "end of file":
        return None

if __name__ == '__main__':
    main()