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Tag: PRNG

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PRNG

Related:
#Random Number Prediction
#Mersenne Twister

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Updated Apr 24, 2026
PRNG Challenges
The future path
pppp4649

pppp4649

Crypto
94 solves
high and low
theoremoon

theoremoon

Crypto
91 solves
XorshiftStream
keymoon

keymoon

Crypto
65 solves
The past or the future?
pppp4649

pppp4649

Crypto
35 solves
Is this Twisted?
yu212

yu212

Crypto
29 solves
janken vs yoshiking 2
theoremoon

theoremoon

Crypto
16 solves
SquareRNG
ptr-yudai

ptr-yudai

Crypto
15 solves
Noisy Channel
yu212

yu212

Crypto
2 solves

high and low

Daily AlpacaHackTopic: RNGReleased: Mar 7, 2026

91 solves
Crypto

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
descriptionsolveswriteups