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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Most Attempted Problems (Past Week)
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4sum 8
prefixsums 5
ancestor 5
adjmatrix 4
closedpath 4

Most Submitted Problems (Past Week)
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obstacles_ioi25 26
cakerun 19
prefixsums 15
oranges2 15
parade 14