Mapper and reducer

mapper2.py

import sys

for line in sys.stdin:
  data = line.strip().split("\t")
  date, time, store, category, cost, payment = data
  print store,"\t",cost

reducer2.py

import sys

maxStore = {}

for line in sys.stdin:
  data = line.strip().split("\t")

  if len(data) != 2:
    continue

  category, sales = data

  sales = float(sales)

  if category in maxStore:
    if maxStore[category] < float(sales):
      maxStore[category] = float(sales)
  else:
    maxStore[category] = float(sales)

for category, sales in maxStore.iteritems():
  print "{0}\t{1}".format(category, sales)