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structure problem (C)

  • 08-04-2003 04:34PM
    #1
    Repli
    Closed Accounts Posts: 3,322 ✭✭✭


    I'm writing a program to use pointers to access structure elements.. When I run this code I get the error "STRUCT-Q2 caused an invalid page fault in module MSVCRT.DLL at 015f:780268b2."
    And in FreeBSD I get "Segmentation fault (core dumped)", after I enter a value for 'a' for the second time - anyone know what the problem is? Thx in advance for any help

    Here is the code: 
    #include <stdio.h>
#include <stdlib.h>
main( int argc, char *argv[] )
{
        struct data
        {
                int a;
                int b;
        };
        
        typedef struct data DATA;
        DATA d;
        DATA *p;
        p = &d;

        printf ("Assign number to a: ");
        scanf ("%d", &d.a);
        printf ("Assign number to b: ");
        scanf ("%d", &d.b);
        printf ("a is %d and b is %d \n \n", d.a, d.b);

        printf ("Assign number to a: ");
        scanf ("%d", p -> a);
        printf ("Assign number to b: ");
        scanf ("%d", p -> b);
        printf ("c is %d and d is %d \n \n", d.a ,d.b);

        printf ("Assign number to a: ");
        scanf ("%d", (*p).a);
        printf ("Assign number to b: ");
        scanf ("%d", (*p).b);
        printf ("a is %d and b is %d \n \n", d.a, d.b);

}


Comments

  • #2
    hussey
    Registered Users, Registered Users 2 Posts: 6,240 ✭✭✭hussey


    me wrong ..


  • #3
    jessy
    Registered Users, Registered Users 2 Posts: 950 ✭✭✭jessy


    printf ("Assign number to a: ");
    scanf ("%d", &d.a);
    printf ("Assign number to b: ");
    scanf ("%d", &d.b);
    printf ("a is %d and b is %d \n \n", d.a, d.b);

    printf ("Assign number to a: ");
    scanf ("%d", &p->a);
    printf ("Assign number to b: ");
    scanf ("%d", &p->b);
    printf ("c is %d and d is %d \n \n", d.a ,d.b);

    printf ("Assign number to a: ");
    scanf ("%d", &(*p).a);
    printf ("Assign number to b: ");
    scanf ("%d", &(*p).b);
    printf ("a is %d and b is %d \n \n", d.a, d.b);

    You Need to put the & operator in the scanf function.

    you have only put it in the first time you got some data from the screen.


  • #4
    Repli
    Closed Accounts Posts: 3,322 ✭✭✭Repli


    D'oh


  • #5
    DeadBankClerk
    Registered Users, Registered Users 2 Posts: 2,281 ✭✭✭DeadBankClerk


    [php]
    printf ("Assign number to a: ");
    scanf ("%d", p).a);
    printf ("Assign number to b: ");
    scanf ("%d", p.b);
    printf ("a is %d and b is %d \n \n", d.a, d.b);
    [/php]

    &(*p) cancels out to just p.


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