Functions and Pointers

[Thegame16]

Hey guys I have just begone learning functions and pointers in class and we were given a question to do for test preparation and I am totally lost.

The question wants me to make a function that asks the user to enter as many integers as possible and if they enter 0 it exits.

conditions:
it ignores all negative numbers
it sums all odd and even numbers separately
it finds the largest integer

The prototype must be int count(int *sumOdd, int *sumEven, int *largest);

b)write another function that prints the report using the prototype:
void printresult(int tot, int sum1, int sum2, int max);

c)call the two functions in the main

sample run:

number:2,number:9,number:12,number:8,number:25,num ber:44, number:0
summary
You entered 6 numbers(excluding 0)
the sum of even is 54
the sum of odd is 34
the largest is 44

This is what I have tried so far but I am very lost, Plz help

#include<stdio.h>

int count(int *sumOdd, int *SumEven, int *largerst);
void printresult(int tot,int sum1,int sum2,int max);




int count(int *sumOdd, int *SumEven, int *largerst)
{
int num,check;
	do{
		printf("Enter as many integers as you like(0 to exit)");
		scanf("%d",&num);
		
		if(num<0)
		{
		
		}
			else if(num%2==0)
			{
			*SumEven=num+num;
			}
				else
				{
				*sumOdd=num+num;
				}
				
		check=check+1;
		
	while(num!=0);
	
	
	return check;
		


}


void printresult(int tot,int sum1,int sum2,int max)
{
printf("You entered %d numbers",tot);
printf("the sum of all the odd numbers is %d",sum1);
printf("the sum of all the even numbers is %d",sum2); 
printf("the largest number is %d",max);
}



int main()
{
count();
printresult();
}

[jimblumberg]

Have you tried to compile your code? Did you get any error messages? If so what are they (Please show complete error messages)? What is your program doing/not doing?

Jim

[Thegame16]

it tells me everything is undeclared in the void printresult function and it tells me that there are to few arguments in the main function and I know that becuase I am not sure how to do that. And I am also missing the sort in the int count function.

[jimblumberg]

Look at your prototype for count:

int count(int *sumOdd, int *SumEven, int *largerst);

and how you are calling it in main()

count();

You must call the functions with the same number and types of parameters.
In main()

int sumOdd,  SumEven,  largerstcount;
count(&sumOdd, &SumEven, &largerstcount) // pass the address of 3 int variables.

You must also pass the variables into your other function.

Jim

[Thegame16]

I just have a couple more questions. By me doing that in the main function it will get all the values that are pointers, but how will it get the return value? Second what do I do with the void printresult in the main function?

[jimblumberg]

You might want to take a look at this link C Tutorial. It has sections on pointers, and defining and using functions.

Jim

[Thegame16]

Ok I got the program to run now. The only problem I am having is a logical one. For the first part I am not sure how I can find out what the largest number is. Second right now the program is priting out crazy answers.

#include<stdio.h>

int count(int *sumOdd, int *SumEven, int *largerst);
void printresult(int tot, int sum1, int sum2, int max);


int main()
{

int sumo,sume,large,a1,a2,a3,a4;
count(&sumo,&sume,&large);
printresult(a1,sumo,sume,large);
}




int count(int *sumOdd, int *SumEven, int *largerst)
{
int num,check,ignore;
	do{
		printf("Enter as many integers as you like(0 to exit)");
		scanf("%d",&num);
		
		if(num<0)
		{
		ignore=num-num;
		}
			else if(num%2==0)
			{
			*SumEven=num+num;
			}
				else
				{
				*sumOdd=num+num;
				}
				
	check=check+1;
		
	}while(num!=0);
	
	
 return check;
		
}





void printresult(int tot, int sum1, int sum2, int max)
{
printf("You entered %d numbers\n",tot);
printf("The sum of of even is %d\n",sum2);
printf("The sum of odd is %d\n",sum1);
printf("the largest number is %d\n",max);
}

I entered in numbers,5 2 and 0.

My result:
4199232 numbers entered
10 is the odd sum
0 is the even sum
-1 is the largest number

[Elysia]

You get crazy results because your code is crazy. Everytime you scan a number, you assign 2 x that number to ignored, even or odd.
check is never initialized. Thus it is not strange you get junk.
ignore is not initialized either and its results are never used.
Your indentation also leaves a lot to be desired.

As for the max value problem, first describe how you would do it if you were given such a problem in reality.

[Thegame16]

You get crazy results because your code is crazy. Everytime you scan a number, you assign 2 x that number to ignored, even or odd.

so what do I have to do to get the continuous numbers they enter to be added as even or odd?

[Elysia]

You obviously need to add the number to the previous sum, no?

[Thegame16]

You obviously need to add the number to the previous sum, no?

like this?

	if(num<0)
		{
		ignore=ignore-num;
		}
			else if(num%2==0)
			{
			*SumEven=*SumEven+num;
			}
				else
				{
				*sumOdd=*sumOdd+num;
				}

when I do this I still have crazy answers, do you know what else is wrong?

[Elysia]

Yes, that's correct. Though I don't know what you're trying to do with ignore.
Also see my edits in my reply above.

[Thegame16]

Yes, that's correct. Though I don't know what you're trying to do with ignore.
Also see my edits in my reply above.

so I initialized check and ignore=0.
For the ignore part I don't want any of those numbers to be added as even or odd.
Now for finding the max value: I know if it was two numbers it would look like this

if(num1>num2)
{
large=num1;
}
     else
     {
      large=num2;
     }

but I don't know how to do it with an infinite amount of numbers possibly being entered/

[Elysia]

If you want to ignore something, then just ignore it. You don't need it, so why add it to a variable in the first place?

Now, imagine yourself being given N numbers written on one piece of paper each, in reality. Describe how you would find the paper containing the largest of those values.

[Thegame16]

compare each number individually and then you would know.