C语言程序设计第四版（何钦铭、颜晖）第十一章指针进阶之删除结点

8. 删除结点:输入若干个正整数(输入-1为结束标志)建立一个单向链表,再输入一个整数m,删除链表中值为m的所有结点。试编写相应程序。

#include<stdio.h> #include<stdlib.h> struct num_node{ int x; struct num_node *next; }; struct num_node *createList(struct num_node *head); struct num_node *Insert_node(struct num_node *head,struct num_node *p); struct num_node *Delete_node(struct num_node *head,int m); void print(struct num_node *head); void free_node(struct num_node *head); int main() { struct num_node *L=createList(NULL); int m; scanf("%d",&m); L=Delete_node(L,m); print(L); free_node(L); return 0; } //创建单链表 struct num_node *createList(struct num_node *head){ int a; struct num_node *p=NULL; scanf("%d",&a); while(a!=-1){ p=(struct num_node*)malloc(sizeof(struct num_node)); p->x=a; p->next=NULL; head=Insert_node(head,p); scanf("%d",&a); } return head; } //插入结点 struct num_node *Insert_node(struct num_node *head,struct num_node *p){ struct num_node *s=head; if(head==NULL){ head=p; s=head; } else{ while(s->next!=NULL){ s=s->next; } s->next=p; s=p; } return head; } //删除指定结点 struct num_node *Delete_node(struct num_node *head,int m){ struct num_node *p=head,*q=head; while(p!=NULL){ if(head->x==m){ head=head->next; q=head; free(p); p=q; } else if(p->x==m){ q->next=p->next; free(p); p=q->next; } else{ q=p; p=p->next; } } return head; } //打印链表 void print(struct num_node *head){ if(head==NULL){ printf("链表已空!\n"); return; } struct num_node *q=head; while(q!=NULL){ printf("%d ",q->x); q=q->next; } } //释放结点 void free_node(struct num_node *head){ struct num_node *q=head,*temp=NULL; while(q!=NULL){ temp=q; q=q->next; free(temp); } }

输入样例：3 2 3 4 3 6 7 8 3 11 3 -1
3

输出结果：2 4 6 7 8 11