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Daily AlpacaHackTopic: RNGReleased: Mar 7, 2026

91 solves
Crypto
Hard

by

theoremoon

theoremoon

guess the high or low!

Beginner Hint 1 (AI-translated)
  • server.py implements a custom RNG called RNG.
  • This RNG is a simplified version of Mersenne Twister, making it easier to predict.
  • The goal of this challenge is to predict this custom RNG and increase money until the flag is printed.
Beginner Hint 2 (AI-translated)
  • To predict the RNG, you need to reproduce the server's RNG state on your own machine.
  • The RNG state consists of state and p.
  • p is easy to predict because it is only incremented each time next_value is called.
  • So what about state?
  • Focus on the fact that x can be recovered from y.
server.py

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