Why??? You might be asking... well, std::endl is the most common thing that might be giving you TLE. It's because std::endl flushes every time. But on the other hand, '\n' only flushes once every 1000 times because is is just a newline character. But if you are used to writing std::endl or endl, you can just make a define for it. #define endl "\n". If you think I am wrong, just comment, don't dislike.