删除两个双向链表中值相同的结点--无空白头结点

有两个双向链表，头指针为：pListA和pListB，要求删除这两个链表中值相同的结点, C语言实现，结点结构如下：

struct node// 双向链表结点{int key;struct node *front, *next;};

完整源代码如下：

/*功能：删除两个双向链表(都不带头结点)中值(key)相同的结点*/#include <stdio.h>#include <stdlib.h>#include <string.h>struct node// 双向链表结点{int key;struct node *front, *next;};/*功能：创建双向链表返回值：1-创建成功，0-创建失败header:创建的双向链表的头指针n:待创建的结点个数*/int createLinklist(struct node **header, int n){int v;struct node *pre, *p;*header = pre = p = NULL;printf("请输入%d个整数：\n", n);while(n-- > 0){scanf("%d", &v);p = malloc(sizeof(struct node));if(p){if(*header == NULL)*header = p;// 设置链表头指针else{pre->next = p;p->front = pre;}p->key = v;p->next = *header;// 新结点的next指向头结点(*header)->front = p;// 更改头结点的front成员pre = p;}elsereturn 0;// 创建链表失败}return 1;// 创建链表成功}// 输出双向链表中的值void displayLinklist(struct node *header){struct node *p = header;if(NULL != p){do{printf("[p = %X]\tdata = %d, front = %X, next = %X\n", p, p->key, p->front, p->next);p = p->next;}while(p != header);printf("\n");}}// 删除双向链表中所有结点并释放空间(头删法)void FreeLinklist(struct node *header){struct node *p;int i = 0;while(header){p = header;if(header->next == header)// 待删除的是最后一个结点header = NULL;else{header->front->next = header->next;header->next->front = header->front;header = header->next;}free(p);}}/*功能：删除双向链表(头指针*pHeader)中值与key相同的结点，从结点*pStart开始向后搜索返回值：如果从双向链表中删除了值为指定key的结点，返回1，否则返回0pHeader:双向链表头指针pStart:从*pStart开始向后搜索，删除值与key相同的结点，直到遇到*pHeaderkey:待删除结点的值注意：调用此函数时，输入参数*pHeader==*pStart，程序将会出错*/int removeNode(struct node **pHeader, struct node **pStart, int key){struct node *p, *temp;int del = 0;p = *pStart;*pStart = NULL;while(p){if(p->key == key){del = 1;temp = p;// temp指向待删除的结点if(*pHeader == temp)// 删除头结点{if(*pHeader == temp->next)// 该头结点是链表的最后一个结点*pHeader = NULL;else{*pHeader = temp->next;p->front->next = *pHeader;// 最后一个结点的next指向新的头结点p->next->front = p->front;// 被删结点的后继结点的front指向被删结点的前驱}p = *pHeader;// p指向新的头结点}else{p->front->next = p->next;p->next->front = p->front;p = p->next;// p指向被删除结点的后继结点}free(temp);}else{ if(*pStart == NULL) *pStart = p; p = p->next;}if(*pStart && p == *pHeader)break;}return del;}// 删除两个链表中值相同的结点void removeEqualNodes(struct node **pHeadA, struct node **pHeadB){struct node *p1, *p2;int del = 0;p1 = *pHeadA;while(p1){p2 = *pHeadB;if((del = removeNode(pHeadB, &p2, p1->key)) == 1){removeNode(pHeadA, &p1, p1->key);}elsep1 = p1->next;if(*pHeadB == NULL || *pHeadA == NULL || (del == 0 && p1 == *pHeadA))break;}}int main(int argc, char *argv[]){struct node *plistA = NULL, *plistB = NULL;int n1, n2;if(argc < 3){printf("Usage: %s <n1> <n2>\n", argv[0]);return 1;}n1 = atoi(argv[1]);n2 = atoi(argv[2]);createLinklist(&plistA, n1);// 创建双向链表createLinklist(&plistB, n2);printf("Before remove:\n");displayLinklist(plistA);// 显示双向链表内容displayLinklist(plistB);removeEqualNodes(&plistA, &plistB);// 删除两个链表中值相同的结点printf("\nAfter remove:\n");displayLinklist(plistA);displayLinklist(plistB);FreeLinklist(plistA);// 释放空间FreeLinklist(plistB);return 0;}