Thread: How should I go about solving this problem?

Originally Posted by ARod609

Write a C function named change() that accepts a floating point number of total coins and the addresses of the integer variables named quarters, dimes, nickels, and pennies.

This is telling you what your function prototype should look like. The function should take 5 arguments, a float (for total coin amount), and 4 pointers to integers (for quarters, dimes, nickels, and pennies).

Originally Posted by ARod609

The function should determine the number of quarters, dimes, nickels, and pennies in the total coins number passed to it and write these values directly into the respective variables declared in its calling function using pointers.

This tells you what the function should do and how it should do it.

Originally Posted by ARod609

Call the function change() from main() three times and print out the contents of the variables quarters, dimes, nickels, and pennies after each function return.

First Call—pass in the total value $1.88 and on return print the contents of
the variables.

Second Call—pass in the total value .32 and on return print the contents
of the variables.

Third Call— ask for a total value input from the keyboard and on return
print the contents of the variables.

This is telling you how to lay out your program, e.g. what your main should look like. Not worded the best, however they want you to make a program that looks something like:

Code:

//your include files

int main(void){
     //the variables you need to make

     call your function with total coin = 1.88
     print your output
     
     call your function with total coin = .32
     print your output

     obtain user input for total coin amount
     call your function with total coin = user inputted value
     print your output

     return (0);
}

Originally Posted by ARod609

1) Math header not sure if i need it...

You do not need it for this problem,

Originally Posted by ARod609

2) Function I am not sure on how to use it correctly...

They want a function. So the prototype would be something like:

void change(float totalcoin, int* quarters, int* dimes, int* nickels, int* pennies);

Originally Posted by ARod609

3) Output did exactly what I was not supposed to do...

A hint for this: most banking software actually stores the amount in a large integer of pennies. So if I were to do something like this I would take the total input and convert it to pennies before I started, e.g. 1.10 would become 110 pennies. After that the operations become pretty simple. Look at what '/' does and what '%' does for math operations.

@Stahta01
I am just trying to learn "C" with the help of the board, I only post a question when I am stumped... Your jokes are funny haha, now I appreciate your advice on writing out the steps and thank you. Everything else is really un called for!

Originally Posted by ARod609

@Stahta01 I know I just dont know how to apply it in "C" lol... so I am lost using the call functions with the modular division (%) to get the remainder to break it down in cents. I thought it would be hot to be able to enter any number and get back the change...

Screw the code... think about the problem... How does making change work?

Lets say you owe someone $0.41 in change...
How much of that can you make up in quarters? (1)
Ok, so you give them a quarter.
How much do you still owe them? ($0.16)
How much of that amount can you make up in dimes? (1)
Ok so you give them a dime.
How much do you still owe them? ($0.06)
How much of that can you make up in nickles? (1)
Give them a nickel, how much is left? ($0.01)
So you give them a penny....

See the problem is you're trying to think about C code, when you haven't even understood the problem itself...

Code:

#include <stdio.h>

void change(float, int *, int*, int*, int*);

int main()
{
	float total;
	int quarters, dimes, nickels, pennies;
    
    {
        total = 1.88;
        
        change(total, &quarters, &dimes, &nickels, &pennies);
        
        printf("TOTAL VALUE ENTERED: %.2f\n", total);
        printf("%9d quarters\n", quarters);
        printf("%9d dimes\n", dimes);
        printf("%9d nickels\n", nickels);
        printf("%9d pennies\n", pennies);
    
        total = 0.32;
        
        change(total, &quarters, &dimes, &nickels, &pennies);
        
        printf("TOTAL VALUE ENTERED: %.2f\n", total);
        printf("%9d quarters\n", quarters);
        printf("%9d dimes\n", dimes);
        printf("%9d nickels\n", nickels);
        printf("%9d pennies\n", pennies);
    
        printf("Enter the amount of money in your pocket:  \n");
        scanf("%f", &total);
        
        change(total, &quarters, &dimes, &nickels, &pennies);
        
        printf("TOTAL VALUE ENTERED: %.2f\n", total);
        printf("%9d quarters\n", quarters);
        printf("%9d dimes\n", dimes);
        printf("%9d nickels\n", nickels);
        printf("%9d pennies\n", pennies);
    }
    return 0;
}
void change(float total, int *quarters, int *dimes, int *nickels, int *pennies)
{		 
    if(total >= 0.25)
        *quarters = (total/0.25);
    
    if(total >= 0.10)
        *dimes = (total - (*quarters * 0.25))/0.10;
    
    if(total >= 0.05)
        *nickels = (total - (*quarters * 0.25) - (*dimes * 0.10))/0.05;
    
    if(total >= 0.05)
        *pennies = (total - (*quarters * 0.25) - (*dimes * 0.10) - (*nickels * 0.05))/0.01;
    
	return ;
}

this is just one of the ways I am trying it now i am going to try a "for" and a "while" statement with "%" division... wish me luck...