RosettaCodeData/Task/Long-multiplication/Python/long-multiplication-3.py

21 lines
483 B
Python

#!/usr/bin/env python
def digits(x):
return [int(c) for c in str(x)]
def mult_table(xs, ys):
return [[x * y for x in xs] for y in ys]
def polymul(xs, ys):
return map(lambda *vs: sum(filter(None, vs)),
*[[0] * i + zs for i, zs in enumerate(mult_table(xs, ys))])
def longmult(x, y):
result = 0
for v in polymul(digits(x), digits(y)):
result = result * 10 + v
return result
if __name__ == "__main__":
print longmult(2**64, 2**64)