P1Q1_Reducer.py

#!/usr/bin/python

# Instead of breaking the sales down by store, instead give us a sales breakdown by product category across all of our stores.

import sys

salesTotal = 0
oldKey = None

# It will be in the format key\tval
# Where key is the store name, val is the sale amount

for line in sys.stdin:
    data_mapped = line.strip().split("\t")
    if len(data_mapped) != 2:
        # Something has gone wrong. Skip this line.
        continue

    thisKey, thisSale = data_mapped

    if oldKey and oldKey != thisKey:
        print oldKey, "\t", salesTotal
        oldKey = thisKey;
        salesTotal = 0

    oldKey = thisKey
    salesTotal += float(thisSale)

if oldKey != None:
    print oldKey, "\t", salesTotal