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22 lines
645 B
Python
22 lines
645 B
Python
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directions = [x.replace('e','e ').replace('w','w ')[:-1].split(' ') for x in open('input').read().splitlines()]
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import math
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import cmath
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def cround(z,n):
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return round(z.real, n)+1j*round(z.imag, n)
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D = {
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'ne': math.sqrt(5)*cmath.exp(1j*math.pi/3),
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'se': math.sqrt(5)*cmath.exp(-1j*math.pi/3),
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'sw': math.sqrt(5)*cmath.exp(-1j*2*math.pi/3),
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'nw': math.sqrt(5)*cmath.exp(1j*2*math.pi/3),
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'e': math.sqrt(5)+0j,
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'w': -math.sqrt(5)+0j
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}
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vectors = []
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for direction in directions:
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vectors.append(cround(sum([ D[x] for x in direction ]),6))
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print(len([x for x in vectors if (vectors.count(x)%2 == 1)]))
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