Welcome to Codebreaker!

Codebreaker is the official platform for Singapore Informatics Olympiad training and contests. We have run selection for the International Olympiad in Informatics for the delegations of Singapore and Indonesia, as well as countless official national and school training programmes.

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party 22
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swayingflowers 15
adjmatrix 14
adjlist 14

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magiccity 58
subgraphs 54
party 54
ballmachine 54
defense101 53