What are the rules involved in debugging? - FORTRAN

What are the rules involved in debugging?

The rule involved in debugging is as follows:

- If strange results are being found then there is possibility of the bug. So, in this case combinations of inputs are tried to get the desired output.

- Code modification is not done until it is sure that there is a bug by checking all the conditions and criteria.

- Modular program is being used that defines the task, which is placed in the debug statements and that can ISOLATE some of the procedure or functioning of the code.

- Use the tools that are being provided with the debugger to check for more options and more output before coming to decision.