# Notebook Intel Atom 1.6 GHz:
# CPython 2.7.5: 1.6 sec
# PyPy 2.0.2: 0.6 sec

def process():
    with open('src.csv') as f:
        content = f.readlines()
    D = {}

    for line in content:
        num, str = line.split(',', 1)
        D[num] = str

    maxLenght = max(len(key) for key in D.keys())


    ins = open('data.dat', 'r')

    r, counter = [], 0
    for line in ins:
        for j in range(maxLenght, 0, -1):
#            PyPy cannot optimize code with variable changing its type,
#           for example,  if we uncomment these 2 lines
#            a = 'asdf'
#            a = 4
#            then PyPy speed will drop to CPython speed
            Tmp = D.get(line[:j], None)
            if Tmp is None: continue
            r.append(line[:-1] +' => '+Tmp)
            break

    ins.close()
    res_file = open('output2.txt', 'w')
    res_file.writelines(r)
    res_file.close()


if __name__ == '__main__':
    from time import time
    t = time()
    process()
    print('time elapsed:', time()-t)