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oliland/gist:4996396

Last active December 14, 2015 00:08
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Solution for "Array Addition 1" on coderbyte. We sort the list of numbers, then pop off the largest. We then walk down the reversed array subtracting until we hit 0 or until we go below 0 - if we go below 0 we skip subtracting that number. If we reach the end of the list and haven't hit 0 yet, then we just pop off the largest number and repeat t…
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gistfile1.py
def array_addition(array):
array = sorted(array)
largest = array.pop()
while (True):
result = largest
for x in reversed(array):
result = result - x
if result == 0:
return True
elif result < 0:
result = result + x
# If we each the end of the list and haven't returned, pop the largest off
try:
array.pop()
except:
return False
def main():
tests = [
([1,2,3,4], True),
([2,6,18], False),
([10,20,30,40,100], True),
([31,2,90,50,7], True),
([2,4,6,12,92], False),
([1,1,1,1,6], False),
([-2,-3,-4,-1,100], False),
([54,49,1,0,7,4], True),
([3,4,5,7], True),
([10,12,500,1,-5,1,0], False)
]
for array, answer in tests:
result = array_addition(array)
if result != answer:
print "WRONG"
else:
print "RIGHT"
if __name__ == "__main__":
main()
@rkiesling
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I was happy to find your code here, but unfortunately I think there may be a problem with the algorithm: try this array: [14,10,3,2,2]. It will add on the 3, but the correct answer requires both 2s but no 3...
Roy

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