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)
Problem Users
helloworld 28
addition 18
sumint 18
maximum 14
prefixsums 12

Most Submitted Problems (Past Week)
Problem Submissions
nicenumber 103
helloworld 75
problemsetter 75
prime 66
segmenttree2 48