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Rows:

CHALLENGEAUTHORS

SOLVES

(CURRENT)

SOLVE RATE

(AT CONTEST TIME)

Welcome
Misc

admin

1459

solves

-

Daily AlpacaHack

1354

solves

-

Daily AlpacaHack

774

solves

-

AlpacaHack Round 2 (Web)

588

solves

Top 28%

= 84/300 users

Daily AlpacaHack

527

solves

-

Daily AlpacaHack

507

solves

-

Daily AlpacaHack

453

solves

-

Daily AlpacaHack

349

solves

-

echo
Pwn

AlpacaHack Round 1 (Pwn)

345

solves

Top 32%

= 56/174 users

Daily AlpacaHack

344

solves

-

Daily AlpacaHack

306

solves

-

Daily AlpacaHack

305

solves

-

Daily AlpacaHack

303

solves

-

Daily AlpacaHack

292

solves

-

Daily AlpacaHack

291

solves

-

Daily AlpacaHack

288

solves

-

Daily AlpacaHack

287

solves

-

Encoding Basics
Misc
Crypto

Daily AlpacaHack

285

solves

-

AlpacaHack Round 7 (Web)

266

solves

Top 15%

= 71/458 users

108
Misc

Daily AlpacaHack

266

solves

-

Rows:

high and low

Daily AlpacaHack
64 solves
Crypto

Author:

guess the high or low!

初åŋƒč€…å‘ã‘ãƒ’ãƒŗãƒˆ1
  • server.py ではį‹Ŧč‡Ēäšąæ•° RNG ãŒåŽŸčŖ…ã•ã‚ŒãĻいぞす。
  • ã“ãŽäšąæ•°ã¯ Mersenne Twister ã‚’į°Ąį•Ĩ化しãĻã€ã‚ˆã‚Šäšąæ•°ä爿¸Ŧをしやすくしたもぎです。
  • ã“ãŽå•éĄŒãŽã‚´ãƒŧãƒĢは、こぎį‹Ŧč‡Ēäšąæ•°ãŽäšąæ•°ä爿¸Ŧã‚’čĄŒã„ã€ money をåĸ—やしãĻフナグをå‡ē力させることです。
初åŋƒč€…å‘ã‘ãƒ’ãƒŗãƒˆ2
  • äšąæ•°ä爿¸Ŧã‚’čĄŒã†ãĢは、ã‚ĩãƒŧバãƒŧぎ RNG ぎįŠļ態を、č‡Ēåˆ†ãŽãƒžã‚ˇãƒŗä¸Šã§å†įžã™ã‚‹åŋ…čĻãŒã‚ã‚Šãžã™ã€‚
  • RNG ぎįŠļ態は state, p です。
  • p は next_value をå‘ŧãŗå‡ēã™ãŸãŗãĢã‚¤ãƒŗã‚¯ãƒĒãƒĄãƒŗãƒˆã•ã‚Œã‚‹ã ã‘ãĒぎで、厚易ãĢä爿¸Ŧできぞす。
  • では、 state はおうでしょうか。
  • y から x ã‚’é€†įŽ—å¯čƒŊであることãĢæŗ¨į›Žã—ãĻください。
server.py
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