FAQ

Why do some Rust bots time out when playing in the IDE but not in the arena?

CodinGame decided to compile Rust programs in debug mode for matches played in the IDE and in release (optimized) mode for arena matches. In Rust, there is an especially large difference between those two modes, because it is common to use high level features like iterators and higher-order functions that are slow in debug mode, but are optimized to very efficient machine code in release mode. In addition, arithmetic operations are checked for overflow in debug mode. Because of those, it is not rare for debug mode to be 10 times slower or more. This means that bots which are fine in the arena can often run out of time in the IDE.