单链表的插入删除

#include <iostream>#include <stdio.h>
#include <stdlib.h>using namespace std;//带头指针的单链表typedef  struct  LNode{int data;struct LNode *next;}LNode, *LinkList;bool InitList(LinkList &L){L = (LNode *) malloc(sizeof(LNode));if(L== NULL){return false;  //内存不足分配失败}L->next =NULL;return true;
}
bool empty(LinkList &L){return  (L->next==NULL);
}bool insert(LinkList &L,int i,int e){if(i<1){return false;}LNode *p = L;int j = 0;while (p!=NULL && j< i-1){p=p->next;j++;}if(p == NULL){return false ;}LNode *s = (LNode *) malloc(sizeof(LNode));s->data = e;p->next = s->next;p->next= s;return true;
}bool deleteN(LinkList &L,int i ,int &e){if(i<1)return false;LNode *p = L;int j = 0;while(p->next!=NULL &&j<i-1){p=p->next;j++;}if(p == NULL){return false;}if(p->next == NULL){return false;}LNode *q = p->next;e = q->data;p->next = q->next;free(q);}int main(){LinkList L;InitList(L);LNode *r= L;for(int i = 1 ; i <= 5 ;i ++){insert( L, i,i);}while(r->next){printf("%d ",r->next->data);r = r->next;}int e =0;deleteN(L,2 ,e);printf("\n%d 被删除\n",e);LNode *w= L;while(w->next){printf("%d ",w->next->data);w = w->next;}free(r);return 0;
}