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In this problem we will crack RSA. Suppose the
parameters for an instance of the RSA cryptosystem are
N = 31313, e = 7.
We have obtained some ciphertext y = 1412.
a) Factor N = 31313 into its constituent primes p and
9.
min(p, q)
max(p, q)
=
b) Compute (N).
(31313)
=
=
c) Compute d, the decryption exponent.
d
X =
=
d) Decrypt y
=
1412 to find the plaintext.

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