链表求和

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

#define N 8

typedef struct list {
    int data;
    struct list *next;
} SLIST;

SLIST *creatlist(int *);

void outlist(SLIST *);

int fun(SLIST *h) {
    SLIST *p;
    int s = 0;
    p = h->next;
    while (p) {
        s += p->data;
        p = p->next;
    }

    return s;
}

int main() {
    SLIST *head;
    int a[N] = {12, 87, 45, 32, 91, 16, 20, 48};

    head = creatlist(a);
    outlist(head);
    printf("\nsum=%d\n", fun(head));
    return 0;
}

SLIST *creatlist(int a[]) {
    SLIST *h, *p, *q;
    int i;
    h = p = (SLIST *) malloc(sizeof(SLIST));

    for (i = 0; i < N; i++) {
        q = (SLIST *) malloc(sizeof(SLIST));
        q->data = a[i];
        p->next = q;
        p = q;
    }
    p->next = 0;

    return h;
}

void outlist(SLIST *h) {
    SLIST *p;
    p = h->next;

    if (p == NULL)
        printf("The list is NULL!\n");
    else {
        printf("\nHead ");
        do {
            printf("->%d", p->data);
            p = p->next;
        } while (p != NULL);
        printf("->End\n");
    }
}