>/Ctf_tasks/rock-paper-scissors $

Estimated reading time: 39 seconds


Category: Crypto

Difficulty: Medium

Description:
The server lets you play a classic game of rock-paper-scissors against itself. At first glance, everything looks fair - but is it really? Your goal is to beat the server 30 times in a row, which might seem impossible... unless you take a closer look at how the server decides its moves. Analyze the server’s behavior, break its randomness, and predict the outcome of future rounds.

Good luck!

Required:

  • Basic understanding of pseudorandom number generators (PRNG)
  • Familiarity with linear congruential generators (LCG)
  • Basic scripting skills

Game Link

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