#!/usr/bin/env python

# Diego Ceccarelli, 2012

from multiprocessing import Pool


def mapFunction(value):
    # work on values
    return (value[0],len(value[1]))

def partition(tuples):
    # marshalll tuples into a dictionary of lists of tuples
    mapping = {}
    for t in tuples:
        try:
            mapping[t[1]].append (t)
        except KeyError:
            mapping[t[1]] = [t]
    return mapping

def reduceFunction(mapping):

    #print mapping
    count = 0
    for node_degree in mapping[1]:
        count += 1
    return (mapping[0],count)

if __name__ == '__main__':
    pool = Pool(processes=10)
    graph = [   (1, [2,3,4,5]),
                (3, [6,10,5]),
                (10,[1,3,4]),
                (2,[3]),
                (4,[3]),
                (5,[10]),
                (6,[1]),
                (7,[1,2,3,4,5,6,8,9,10]),
                (8,[1,2,3,4,5,6,7,9,10]),
                (9,[1])
            ]
    print "GRAPH:"
    for node in graph :
        print node[0],"->",node[1]


    tuples = pool.map(mapFunction, graph)
    mapping = partition(tuples)
    results = pool.map(reduceFunction, mapping.items())
    print "------"
    print "DEGREEs"
    for res in results:
        print "Degree: ",res[0], "\tFrequency",res[1]