Fix C floor Function Invalid Parameter Use

If encountering invalid cases when using the floor function in C language, it may be due to the parameter being passed not meeting the requirements. The floor function accepts a parameter of type double, and if an invalid parameter is passed, it may cause the function to not work properly.

Ways to solve this problem include:

1. Ensure that the incoming parameter is of type double. If it is not, you can use type casting to make sure the parameter type is correct.
2. Check if the input parameters are within the valid range defined by the floor function. The floor function is typically used for rounding down, and if the input parameter is infinity or negative infinity, it may result in an invalid outcome.
3. Checking if the input parameters are NaN (Not a Number) can also result in the floor function returning invalid results.

By checking and handling the incoming parameters using the above method, invalid situations when using the floor function in C can be avoided.