31 lines
787 B
Python
31 lines
787 B
Python
import sys, re
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def gcd(a, b):
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if b == 0:
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return 1, 0, a
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x, y, d = gcd(b, a % b)
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x = y
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y = (d - x*a) // b
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return x, y, d
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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 euclid.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)[2]
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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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u, _, _ = gcd(a1, m1)
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x0 = b1*u
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s = ""
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for i in range(0, 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 euclid.py '7x=8mod13'")
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sys.exit(1)
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print(solve(sys.argv[1])) |