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  • Extended GCD
    20 pts · 18598 Solves · 74 Solutions
    Let $a$ and $b$ be positive integers.

    The extended Euclidean algorithm is an efficient way to find integers $u,v$ such that

    $a \cdot u + b \cdot v = \gcd(a,b)$

    Later, when we learn to decrypt RSA ciphertexts, we will need this algorithm to calculate the modular inverse of the public exponent.

    Using the two primes $p = 26513, q = 32321$, find the integers $u,v$ such that

    $p \cdot u + q \cdot v = \gcd(p,q)$

    Enter whichever of $u$ and $v$ is the lower number as the flag.

    Knowing that $p,q$ are prime, what would you expect $\gcd(p,q)$ to be? For more details on the extended Euclidean algorithm, check out this page.

    You must be logged in to submit your flag.


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