30 lines
619 B
Python
30 lines
619 B
Python
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def reversible(n):
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n_rev_str = str(n)[::-1]
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if n_rev_str.startswith("0"):
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return False
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n_rev = int(n_rev_str)
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ds = str(n + n_rev)
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for d in ds:
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if int(d) % 2 == 0:
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return False
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return True
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def euler_145():
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# pure bruteforce, took about four minutes wity pypy
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count = 0
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counted = set()
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for i in range(10**9):
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if not i in counted and reversible(i):
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count += 1
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counted.add(i)
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return count
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if __name__ == "__main__":
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solution = euler_145()
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print("e145.py: " + str(solution))
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assert(solution == 608720)
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