#!/usr/bin/python
#    Copyright (C) 2012 Jeff Epler
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
import sys

# XXX somehow make this smarter so that e.g., du -h works as input
val = int
sub = lambda a, b: a-b
show = lambda v: "%d" % v

def read_du(f):
    if f == "-": f = sys.stdin
    else: f = open(f)
    d = {}
    for line in f:
	v, k = line.strip().split(None, 1)
	d[k] = val(v)
    return d

d1 = read_du(sys.argv[1])
if len(sys.argv) > 2:
    d2 = read_du(sys.argv[2])
else:
    d2 = read_du('-')

while d1:
    k, v1 = d1.popitem()
    if k in d2:
	v2 = d2.pop(k)
    else:
	v2 = 0
    dv = sub(v2, v1)
    if dv:
	print "%s\t%s" % (show(dv), k)
while d2:
    k, v2 = d2.popitem()
    print "%s\t%s" % (show(dv), k)