Please Help

Hi Mentors,

Please help me with the following code,

Code:

#include<stdio.h>
void main()
{
int num1, num2;
int sum,diff,prod;
void getNum(int * , int *);
getNum(&num1,&num2);
sum = num1+num2;
printf("Sum is=%d",sum);
getNum(&num1,&num2);
diff= num1-num2;
printf("diff  is=%d",diff);
getNum(&num1,&num2);
prod= num1*num2;
printf("Prod is=%d",prod);
}

void getNum(int *x, int *y)
{
 printf("Enter num1=");
 scanf("%d", *x);
 printf("Enter num2=");
 scanf("%d", *y);
}

I am not getting the correct output, the number i am entering in the *x and *y is getting negative, i have tried turbo C/C++ and gcc(segmentation fault).

Please help

Here's what you should be seeing if you're compiling with gcc

$ gcc -Wall -Wextra foo.c
foo.c:2: warning: return type of ‘main’ is not ‘int’
foo.c: In function ‘getNum’:
foo.c:21: warning: format ‘%d’ expects type ‘int *’, but argument 2 has type ‘int’
foo.c:23: warning: format ‘%d’ expects type ‘int *’, but argument 2 has type ‘int’

You already have pointers to ints in getNum, there is no need for any further & or * decoration.

Hi,

I didn't get your point, can you please explain the same briefly.

Thanks
Ankit

Your problem is withing function:

Code:

void getNum(int *x, int *y)
{
 printf("Enter num1=");
 scanf("%d", *x);                    it should look like this :   scanf("%d", x);   
 printf("Enter num2=");
 scanf("%d", *y);                                                 scanf("%d", *y);


}

Originally Posted by Diablo667

Your problem is withing function:

Code:

void getNum(int *x, int *y)
{
 printf("Enter num1=");
 scanf("%d", *x);                    it should look like this :   scanf("%d", x);   
 printf("Enter num2=");
 scanf("%d", *y);                                                 scanf("%d", *y);


}

Hi,

Thanks a lot for the suggestion, though this solved the problem I was having but I am still doubtful why did it worked, as *var refers value at the address stored in <var>, while var stores the address of the another integer variable.

Please correct me if I am wrong, thanks

Originally Posted by ankiit

Hi,

Thanks a lot for the suggestion, though this solved the problem I was having but I am still doubtful why did it worked, as *var refers value at the address stored in <var>, while var stores the address of the another integer variable.

Please correct me if I am wrong, thanks
[/LEFT]

You are mainly right; but, scanf wants the address to store the result.

Tim S.

Originally Posted by stahta01

You are mainly right; but, scanf wants the address to store the result.

Tim S.

Hi Tim,

Thanks a lot , got your point.

regards,
Ankit