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warning: comparison between pointer and integer

Hello all,

I'm still quite new to programming, and are merely trying to create a program to calculate and display the Sum and Average of an array of values. However, when I compile I get the Error:
AverageWorking1.c:43:6: warning: comparison between pointer and integer
AverageWorking1.c:43:15: warning: comparison between pointer and integer

Line 43: if (n>100 || n<2)

Code:

#include <stdio.h>



int main()

{

        int n, temp, i=0;

        float num[100], sum=0.0, average;

        char c;



printf("This program calculates the Sum and Average of an array of values.\nEnter the number of        values in the array(2-100): ");



if(GetUserInput(&n))

{

if(temp!=1)

        while(i<n)

                {

                ++i;

                printf("%d. Enter number: ",i);

                scanf("%f",&num[i]);

                sum+=num[i];

                }



        average=sum/n;

        printf("Sum = %.2f\n",sum);

        printf("Average = %.2f\n",average);



return 0;

}

}



int GetUserInput(int* n)

{

        int temp;

        char c;



        temp =        scanf("%d", n);

        while((c = getchar()) != '\n' && c != EOF);



if(temp!=1)

        {

          printf("Error! Number should be in range of (2 to 100)\n");

        return 0;

        }

if (n>100 || n<2)

        {

          printf("Error! Number should be in range of (2 to 100).\n");

        return 0;

        }



return 1;

}

Exactly what it says on the tin! "n" is a pointer...

Quote:

Originally Posted by Mr Oblivion (Post 4900001)

Since within your GetUserInput function, "n" is a pointer to an integer, you need it to say

Code:

if (*n>100 || *n<2)

so that the compiler knows you want to look at the value pointed to by "n", not the pointer "n" itself.

so n is a pointer. It holds the location in memory where a value lives. n does NOT contain the number. It "points" to where a number is.

To make this work, the if statements shoudl just be changed to reference "*n" instead of "n", but I would personally look to make GetUserInput(int* n) take the n directly instead (your &n when calling it creates the pointer reference) so tweaks like:

if(GetUserInput(&n)) ---> if(GetUserInput(n))
GetUserInput(int* n) ---> GetUserInput(int n)
temp = scanf("%d", n); ---> temp = scanf("%d", &n);

etc.

Note that you've used scanf differently here, once time you give it the variable, num, the other you create a pointer reference from n, &n.

Ah, of course!

Thank you for all the help!
I feel such a fool, but I am still getting used to pointers. :L

-Mr Oblivion