30 lines
786 B
Python
30 lines
786 B
Python
from gmpy2 import mpz
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def extended_gcd(a, b):
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if b == 0:
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return (a, mpz(1), mpz(0))
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else:
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gcd, x1, y1 = extended_gcd(b, a % b)
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x = y1
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y = x1 - (a // b) * y1
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return (gcd, x, y)
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def modinv(b, n):
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gcd, x, y = extended_gcd(b, n)
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if gcd != 1:
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raise ValueError(f"Odwrotność modulo nie istnieje, ponieważ gcd({b}, {n}) = {gcd} ≠ 1.")
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else:
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return x % n
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n = mpz(input("Podaj n: "))
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b = mpz(input("Podaj b: "))
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try:
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inverse = modinv(b, n)
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print(f"Odwrotność {b} modulo {n} to {inverse}.")
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if (b * inverse) % n == 1:
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print(f"Sprawdzenie: ({b} * {inverse}) mod {n} = 1\n")
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else:
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print("Błąd w obliczeniach.\n")
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except ValueError as e:
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print(f"Dla b = {b}, n = {n}: {e}\n") |