Error “Time Limit Exceeded”, what to do?

We look for optimal algorithms in your solutions. Every problem has a time limit with respect to its optimal solution. 

If your code could not produce the required output within the set time limit, you get a “Time Limit Exceeded” error. 

Test cases get progressively larger, so it is common for a naive solution to pass the first few (smaller) test cases and then fail when confronted with the bigger ones.