This repository has been archived on 2021-10-31. You can view files and clone it, but cannot push or open issues or pull requests.
ProgrammingChallenges/charging_chaos.py

67 lines
1.4 KiB
Python
Raw Normal View History

#!/usr/bin/env python3
# Inspired by descriptive part of oldest answer in
# https://stackoverflow.com/questions/23308954
def try_flips(Outlets, Devices, nDev, l):
# Try all the devices in all the outlets
# Find the flip configurations in bitwise form
# that are compatible (present) in all the outlets
S = set()
for j in range(len(Devices)):
S.add(Outlets[0] ^ Devices[j])
for i in range(1, len(Outlets)):
row = set()
for j in range(len(Devices)):
row.add(Outlets[i] ^ Devices[j])
S = S.intersection(row)
# If no common configuration is found, then no flip can
# solve this case
if len(S) == 0:
return "NOT POSSIBLE"
# Otherwise, pick the one with the smallest number of 1s
# (which represent flips) and return the number of flips
m = None
for s in S:
b = count_bits(s)
if m is None or b < m:
m = b
return str(m)
def count_bits(x):
i = 0
while x != 0:
i = i + (x & 1)
x = x >> 1
return i
def read_switches():
O = input().split()
for i in range(len(O)):
O[i] = int(O[i], 2)
return O
if __name__ == "__main__":
t = int(input())
for i in range(t):
line = input().split()
n, l = int(line[0]), int(line[1])
Outlets = read_switches()
Devices = read_switches()
print("Case #" + str(i + 1) + ": " + try_flips(Outlets, Devices, n, l))