Need function to show values

I wrote code that store value at each function call.

Code:

---

#include<stdio.h>
#include<stdlib.h>


int *foo ( int *P, int V)
{
    int *N = malloc (sizeof(*N));


    if ( N != NULL)
    {
        *N = V;
    }
}


int main()
{
  int *P = NULL;
  P = foo ( P, 1);
  P = foo ( P, 2);
  P = foo ( P, 3);
  P = foo ( P, 4);
 
    return 0; 
}

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I want to write a function that print values. I don't know how to do it with function

You seem to be thinking of something like this:

Code:

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#include <stdio.h>
#include <stdlib.h>
 
typedef struct N
{
    int v;
    struct N *x;
} N;
 
N *add(N *r, int v)
{
    N *n = malloc(sizeof *n);
    if (!n) { perror("add"); exit(1); }
    n->v = v;
    n->x = r;
    return n;
}
 
void print(const N *r)
{
    for ( ; r; r = r->x) printf("%d ", r->v);
    printf("\n");
}
 
int main()
{
    N *r = NULL;
    r = add(r, 1);
    r = add(r, 2);
    r = add(r, 3);
    r = add(r, 4);
 
    print(r); // values are printed in reverse order since 'add'
              // adds new elements to the head of the list
 
    return 0;
}

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you are talking about pointer to structure Whereas in my code there is a pointer to integer

Can I see the values stored in my program with the help of a function?

john.c introduced a struct type in order to construct a linked list, i.e., struct N represents a linked list node. This way, you can store the values in a linked list and thereby loop over the linked list in order to show them.

You could say, store the pointers in an array of pointers instead, and thereby loop over the array in order to show the values that the pointers point to. For example:

Code:

---

#include <stdio.h>

int *foo(int value)
{
    int *p = malloc(sizeof(*p));
    if (p)
    {
        *p = value;
    }
    return p;
}


void print_values(int *values[], size_t num)
{
    for (size_t i = 0; i < num; ++i)
    {
        if (values[i])
        {
            printf("%d\n", *values[i]);
        }
    }
}


int main(void)
{
    int *p[4];
    p[0] = foo(1);
    p[1] = foo(2);
    p[2] = foo(3);
    p[3] = foo(4);

    print_values(p, sizeof(p) / sizeof(p[0]));

    // free what you malloc here
    // ...

    return 0;
}

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