How to return more than one counter variable from a function in C-CodePudding

I am very new to programming with C, please do bear with me if I sound off at any point. I am trying to return two int variable, whose values are required in another function.

here is an idea of what I want :

#include <cs50.h>
#include <stdio.h>

typedef struct {
int sum,digit;
}twoInts  ;

// prototype functions
twoInts sumCardDigit(long d);

int main(void)
{
    //digit below is used to check for even and other positions
    long cardNum = get_long("Enter card number :");
    twoInts values = sumCardDigit(cardNum);

printf("values: %d\n",values.sum)
}

 twoInts sumCardDigit(long cardNum)
{

int sumeven = 0, sumodd = 0,digit = 0, sum = 0;
    int rem = cardNum % 10;
    digit  ;

    //if digit is even
    if (digit % 2 == 0)
    {
        int multiply = rem * 2;
        if (multiply == 0)
        {
            sumeven  = multiply;
        }

        else
        {
            //adding all digits after
            while (multiply != 0)
            {
                sumeven  = multiply % 10;

                //minus last digit of multiply
                multiply /= 10;
            }
        }
    }
    else //if digit is odd
    {
        sumodd  = rem;
    }

     //minus last digit from cardNum

    cardNum /= 10;

    sum  = sumeven   sumodd;
    struct twoInts s;
s.sum;
s.digit

}


return s;

}

I want a situation where both the sum and digit's value can be used elsewhere in my program.

CodePudding user response：

There are a few problems at the end of your sumCardDigit function:

The end of the function should look like this:

  ...
  sum  = sumeven   sumodd;

  twoInts s;         // remove `struct`, twoInts has been typedefed so it's 
                     // wrong to use struct

  s.sum = sum;       // you forgot the assignment
  s.digit = digit;   // you forgot the assignment

                     // there was a `}` thet didn't belong here

  return s;
}

Now your code should compile, but I don't know if the code is actually correct.

CodePudding user response：

You can only return one thing at a time in C. The method you follow is correct one of using a struct. Wherever you are using these value, you will have to get both sum and digit from this struct.