Why Codechef online IDE is showing 'Time Limit Exceeded' but same solution is accepted when submitted?

When i compile and run a C program in my Dev C++ IDE it is giving right execution time. And I submitted the code for a practice problem. The Answer was Accepted. But just to see how Codechef Online IDE works, I run the same code. But I shows more execution time and time limit exceeded.

So Can anyone please explain why this is happening?

This sometimes happens if i don’t insert any test cases in the online IDE. Like a program to take two inputs to add and if no input is given the program may simply wait for input.

If they don’t add test cases to IDE then what is the use of their Online IDE. I can’t understand.

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