C++/C conversion to just C

[Alterah]

Set a break point at

 int Finished = 0;

and step from there. The problem should show up after a couple of steps. Also...your formatting for the switch statement...seems rather odd to me. I would do something like:

            switch  (choice)
            { 
                // accesses the functions
                case 0: 
                    Finished = 1;                     
                    break;
                case 1: 
                    addition(&reward);                
                    break;
                case 2: 
                    subtraction(&reward);             
                    break;
                default : 
                    printf("Error in input\n\n");   
                    break;
            }

Sure, it is more lines of code, but imagine each of the cases requiring 10 instructions. I think the way I have it above would be more clear. But, that is just a personal preference.