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    The Chess Move Validation hole will go live in approximately . Why not try and solve it ahead of time?

    Recent Solutions

    Hole Golfer Bytes Time Submitted
    Chess Move Validation bpharaldsson 175
    Forsyth–Edwards Notation bpharaldsson 218
    Chess Move Validation tomh1012 160
    PalindromemordnilaP bpharaldsson 286
    Alphabetic Numbers bpharaldsson 213
    Calendar codewrite 309
    Chess Move Validation AdrienHache 142
    Reverse Polish Notation michelebastione 229
    Thue–Morse Constant AdrienHache 113
    Fizz Buzz michelebastione 90
    Hexdump michelebastione 217
    Calendar michelebastione 262
    Thue–Morse Constant HumanoidCPU 1,020
    Scrambled Sort michelebastione 263
    Forsyth–Edwards Notation michelebastione 204
    Lucky Numbers michelebastione 150
    Thue–Morse Constant bitsandbeyond 149
    Cubes codewrite 390
    𝑒 michelebastione 125
    Thue–Morse Constant namelessiw 121
    DFA Simulator codewrite 359
    Factorial Factorisation michelebastione 182
    Hexagonal Spiral bitsandbeyond 229
    Pernicious Numbers (Long) michelebastione 92
    Pernicious Numbers michelebastione 65
    QR Decoder codewrite 365
    π egu555 215
    Tutorial quasar098 372
    Fibonacci codewrite 58
    Poker Yax42 397
    Poker namelessiw 🥉 329
    Zodiac Signs codewrite 266
    Sudoku (Fill-in) codewrite 957
    Sudoku codewrite 1,325
    Star Wars Opening Crawl codewrite 1,198
    Musical Chords codewrite 661
    Forsyth–Edwards Notation codewrite 278
    Reversi codewrite 388
    Set codewrite 313
    Hilbert Curve codewrite 1,296
    Ten-pin Bowling codewrite 639
    Morse Encoder codewrite 434
    Zeckendorf Representation codewrite 199
    SI Units codewrite 1,273
    CSS Colors codewrite 250
    Catalan Numbers JOrE20 86
    Fractions codewrite 240
    ROT13 tomh1012 105
    Ulam Sequence tomh1012 174
    Emojify codewrite 254
    Poker codewrite 1,026
    Spelling Numbers namelessiw 347
    Mahjong codewrite 1,407
    Spelling Numbers bitsandbeyond 374
    Proximity Grid codewrite 731
    Maze codewrite 736
    Seven Segment codewrite 219
    Jacobi Symbol codewrite 226
    Inventory Sequence codewrite 198
    Smith Numbers codewrite 216
    Rijndael S-box codewrite 311
    Taxicab Numbers codewrite 222
    Farey Sequence codewrite 118
    Kolakoski Constant codewrite 338
    Kolakoski Sequence codewrite 144
    Foo Fizz Buzz Bar scpchicken 133
    Gijswijt’s Sequence scpchicken 2,018
    Kaprekar Numbers codewrite 121
    Gijswijt’s Sequence codewrite 289
    Seven Segment bitsandbeyond 121
    Lyndon Factorization AdrienHache 154
    Taxicab Numbers Yax42 138
    Catalan Numbers scpchicken 82
    Tongue-twisters zzh1996 343
    Diamonds KasperKivimaeki 107
    Binary Lambda Calculus bitsandbeyond 421
    24 Game bitsandbeyond 406
    ISBN namelessiw 🥇 82
    Odious Numbers (Long) michelebastione 66
    Odious Numbers michelebastione 65
    Evil Numbers michelebastione 65
    Evil Numbers (Long) michelebastione 66
    Arithmetic Numbers KasperKivimaeki 94
    Look and Say codewrite 179
    Morse Decoder namelessiw 🥈 159
    Maze Yax42 🥉 136
    π codewrite 187
    Alphabetic Numbers amazingalek 310
    Billiards namelessiw 🥇 181
    Ulam Sequence amazingalek 313
    Factorial Factorisation scpchicken 1,001
    Evil Numbers (Long) scpchicken 494
    Emojify scpchicken 908
    Intersection Yax42 169
    Billiards Yax42 🥇 181
    DFA Simulator tomh1012 256
    Medal Tally Yax42 💎 146
    Catalan Numbers KasperKivimaeki 🥇 79
    Catalan Numbers albanian-laundromat 86
    N Queens edsrzf 🥈 147