40 lines
971 B
Python
40 lines
971 B
Python
import sys, re
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def gcd(a, b):
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while b != 0:
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b, a = a % b, b
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return a
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def euler(n):
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result = n
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p = 2
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while p * p <= n:
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if n % p == 0:
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while n % p == 0:
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n //= p
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result -= result // p
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p += 1
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if n > 1:
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result -= result // n
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return result
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def solve(task):
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f = re.fullmatch(r'(\d+)x=(\d+)mod(\d+)', task)
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if f == None:
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return "Usage Example: py euler.py '7x=8mod13'"
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a, b, m = int(f.groups()[0]), int(f.groups()[1]), int(f.groups()[2])
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d = gcd(a, m)
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if d > 1 and b % d != 0:
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return 'No solutions'
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a1, b1, m1 = a // d, b // d, m // d
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x0 = (b1 * pow(a1, euler(m1) - 1, m1)) % m1
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s=''
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for i in range(d):
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s += f'x={(x0+m//d*i)%m}mod{m}\n'
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return s[:-1]
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if __name__ == "__main__":
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if len(sys.argv) != 2:
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print("Usage Example: py euler.py '7x=8mod13'")
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sys.exit(1)
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print(solve(sys.argv[1])) |