链表 c

// linkedLinearList.c

#include <stdio.h>
#include "ds.h"

typedef int ElemType;

typedef struct LNode{
  ElemType data;
  struct LNode *next;
}LNode, *LinkList;

/*
 InitLinkList
*/
Status InitList(LinkList *l){
  // head point, make l point to it
  *l = (LinkList)malloc(sizeof(LNode));
  if(!*l)exit(OVERFLOW);
  (*l)->next = NULL;
  return OK;
}

/*
 Args:
  l: linked list with head node
  i: deliver ith element to e if exists and return OK
     else, return ERROR
*/
Status GetElemLinkList(LinkList l, int i, ElemType *e){
  LNode *p = l->next; // point to first node
  int j = 1;
  while(p && j < i){
    p = p->next;
    j++;
  }
  if(!p || j > i)return ERROR;
  *e = p->data;
  return OK;
} // GetElem

/*
 Insert e into l at position i.
 Args:
  l: linked list with head node
*/
Status InsertLinkList(LinkList l, int i, ElemType e){
  LNode *p = l;
  int j = 0;
  while(p && j < i-1){ // find position i-1
    p = p->next;
    j++;
  }
  // j > i-1: make sure, i>=1, if i = 0, return ERROR
  if(!p || j > i-1)return ERROR;

  LNode *new_node = (LNode *)malloc(sizeof(LNode));
  new_node->data = e;
  new_node->next = p->next;
  p->next = new_node;
  return OK;
}

Status DeleteLinkList(LinkList l, int i, ElemType *e){
  LNode *p = l;
  int j = 0;
  while(p && j < i-1){
    p = p->next;
    j++;
  }// while end
  if(!p->next || j > i-1){
    return ERROR;
  }// if end
  LinkList q;
  q = p->next;
  p->next = q->next;
  *e = q->data;
  free(q);
  return OK;
}

/*
 print link list
*/
Status PrintLinkList(LinkList l){
  LinkList p = l->next;
  while(p){
    printf(" %d ", p->data);
    p = p->next;
  }
  printf("\n");
  return OK;
}

int main(){
  // Initial link list
  LinkList l;
  InitList(&l);

  // insert
  int j, a[7]={2,6,8,9,11,15,20};
  for(j=0; j<6; j++)
    InsertLinkList(l, j+1, a[j]);
  printf("LinkList l = ");
  PrintLinkList(l);

  // delete
  ElemType tmp;
  DeleteLinkList(l, 2, &tmp);
  printf("LinkList l = ");
  PrintLinkList(l);
  printf("Deleted element tmp = ");
  printf("%d\n", tmp);

}

/* ds.h */
/* Some pre define */
#ifndef _HS_H
#define _HS_H

#include <string.h>
#include <ctype.h>
#include <sys/malloc.h>
#include <stdio.h>
#include <stdlib.h>

/* State code */
#define TRUE 1
#define FALSE 0
#define OK 1
#define ERROR 0
#define INFEASIBLE -1
#define OVERFLOW 0

typedef int Status;
typedef int Boolean;

#endif

./a.out 
LinkList l =  2  6  8  9  11  15 
LinkList l =  2  8  9  11  15 
Deleted element tmp = 6