Passing multiple arguments for function to take in

[MKANET]

I have played this part of "Lesson 18: Arguments and Return Values" video more times that I'm willing to admit.  However, I just can't figure out what happens to each argument taken in by the function and why.

The way I see this (which is completely wrong):

No matter what value is sent to the function's local variable iInt2, the value will always change to 1.
Also, no matter what value is sent to the function's local variable iInt3, the value will always change to 0.
The only instance where the function's local variable doesn't override the value sent to it is iInt1.

Hence:

The value 4 processed by function Sum, will = 5    (because 4 + 1 + 0 = 5)
The values 4, 3 processed by function Sum, will be = 5 (because 4 +1 + 0 =5)
The values 4, 3, -6 processed by function Sum, will be = 5 (because 4 +1 + 0 =5)

5
5
5

So... what does really happen?  I'm trying to comprehend this in a way that makes more sense that the above.

[Michael Hall]

When 4 is passed in, the default values are used for the last two parameters: 4+1+0=5. When 4 and 3 are passed in the 3 is used instead of the default value of 1 for iInt2. So, you get 4+3+0=7. When 4, 3, and -6 are passed in, none of the default values are passed in. So, iInt1 = 4, iInt2 = 3 and iInt3 = -6 and you get 4+3+(-6)=1.

I hope that clears it up. If you still have questions, please ask. 

Mike

[MKANET]

It completely clears it up.  I didn't realize that the local variables declared in the function will only use the predefined default mathematical operators if no value is passed for that argument.  That's definitely good to know.

BTW As I'm getting used to using new C++ terminology, please feel free to correct my sentences even if I still manage to get the point across.

Thanks!