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Start Of Program
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This C++ program demonstrates RSA (Rivest–Shamir–Adleman) encryption and decryption.

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STEP_0: Key Generation

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p = 1283 // first prime number

q = 2789 // second prime number

n = p * q = 3578287 // the modulus in both the encryption and the decryption processes

phi = (p - 1) * (q - 1) = 3574216 // Euler's Totient function: ϕ(n) = (p − 1) * (q − 1)

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STEP_1: Choose e such that 1 < e < phi and gcd(e, phi) = 1

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e = 1916677 // public exponent

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STEP_2: Compute the private key (d)

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d = 1313549 // such that (e ∗ d) % ϕ(n) = 1

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STEP_3: Display the public and private keys

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Public Key: (1916677, 3578287)

Private Key: (1313549, 3578287)

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STEP_4: Encrypt a message (m must be less than n)

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The value which was entered for m is 3578287.

m has been reset to 3578286 due to the fact that the input value for m was either less than one or else greater than 3578286.

c = (m ^ e) % n = 3578286 // encryption such that m = (c ^ d) % n

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STEP_5: Decrypt the message

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decrypted_message = 3578286 // such that m = (c ^ d) % n

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End Of Program
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