pset1: cash: How to deal with undeclared variables?

Question

A warning: I know there must be an easier way to make this script work. But I'm a newb who has a very hard time wrapping my head around programming and I don't want to destroy my thinking by looking at the answers.

Any who. I'm having a bunch of undeclared variable issues in my script. I'm not sure how to make them "universal" so that it stops being such a nuissance.

Any examples or advice on how to make it work for my script ?

Thanks

I think the image above is the only functional part of my script.

Here's the broken part:

also I realized that the last line should be %i since i'm adding integers. but its too cumbersome a task to recapture that image.

Answer 1

I think you'd benefit from a thorough review of class material, particularly the discussion on variable scope.

The "undeclared" vars are really an issue of where they are declared. Remember that a variable only exists between the immediate pair of curly braces surrounding it. A var can go into and back out of a set of braces, but it will cease to exist after the closing curly brace that defines its scope. A visual example explains it better.

int main(void)
{
    int i;
    {
       int j;
       // both i and j exist here.
    }
    // j no longer exists, but i still does exist here.
}
// both i and j no longer exist here. 

Also, keep an eye on parentheses pairings ().

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