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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prefixsums 25
helloworld 13
card 12
addition 12
entropy 11

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prefixsums 108
trivialexam 61
elevator 60
landmarks 50
entropy 47