common_friends.py

#python common_friends.py friend.txt -q
from mrjob.job import MRJob
from mrjob.step import MRStep
from itertools import chain

class MAPR(MRJob):
    def mapper(self, _, line):
        p=line.split(" : ")
        f=sorted(p[1].split())
        for p2 in f: yield(sorted([p[0],p2]),f)

    def reducer(self, key, values): 
        values=list(values)
        yield(key,sorted(list(set(values[0]) & set(values[1]))))

    # ["A", "B"] ["C", "D"]
    # ["A", "C"] ["B", "D"] 
    # ["A", "D"] ["B", "C"] 
    # ["B", "C"] ["A", "D", "E"] 
    # ["B", "D"] ["A", "C", "E"] 
    # ["B", "E"] ["C", "D"] 
    # ["C", "D"] ["A", "B", "E"] 
    # ["C", "E"] ["B", "D"] 
    # ["D", "E"] ["B", "C"]  


 


if __name__ == '__main__':
    MAPR.run()

euler_path.py

#python common_friends.py konigsberg.txt -q
from mrjob.job import MRJob
from mrjob.step import MRStep
from itertools import chain

def len(iterable):
    try:
      return iterable.__len__()
    except AttributeError:
      return sum(1 for _ in iterable)

class MAPR(MRJob):
    def mapper(self, _, line):
        p=line.split()
        yield(p[0],p[1])
        yield(p[1],p[0])

    def combiner(self, key, values): 
        l=list(values)
        yield('euler',[int(key),len(l)])

    def reducer(self,key, values):
        values=list(values)
        euler=True
        for v in values:
            yield(v[0],v[1])
            if (v[1]%2)==1: euler=False
        yield('euler',euler)


if __name__ == '__main__':
    MAPR.run()
    

friends.txt

A : B C D
B : A C D E
C : A B D E
D : A B C E
E : B C D

jumble.py

#python common_friends.py jumble.txt -q

from mrjob.job import MRJob
from mrjob.step import MRStep
from itertools import permutations

diction=set(line.strip() for line in open('sowpods.txt'))

class MAPR(MRJob):
    def mapper(self, _, line):
        w=line.split()[0]
        for p in set(permutations(w)):
            yield('?'+w,''.join(p))

    def combiner(self,key, values):
        for v in values:
          if(v in diction):
            if(v!=key[1:]):yield(key,v)

    def reducer(self, key, values):  
        values=sorted([key]+list(values))
        yield(len(values),values)

if __name__ == '__main__':
    MAPR.run()
    

jumble.txt

laisa ?
laurr ?
bureek ?
prouot ?
clofa ?
circle ?
mursee ?
mirpte ?
velga ?
pluit ?
siccur ?
impage ?

konigsberg.txt

1 0
0 1
0 2
1 2
2 3
1 3
3 1