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@tos-kamiya
Last active August 29, 2015 14:01
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brute force solution for a math question
#coding: utf-8
import sys
import itertools
write = sys.stdout.write
nums = [i for i in range(1, 9+1)]
for hidden in itertools.combinations(nums, 2):
shown = list(sorted(set(nums) - set(hidden)))
assert len(shown) == 7
for num_on_blackboard in range(10, 99+1):
mod_0_stus = 0
for stu in shown:
possible_nums = [stu] + list(hidden)
if all(num_on_blackboard % pn == 0 for pn in possible_nums):
mod_0_stus += 1
if mod_0_stus == 5:
write("hidden = %s\n" % list(hidden))
write("num on blackboard = %d\n" % num_on_blackboard)
write("\n")
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