我最近学习了Tries算法，并且正在努力使用链表实现它。我已经完成了数组实现并且工作正常。
我期待树的话 （熊，床，公牛，买入，买入，卖出，股票，止损）将被创建如下：
/
|
b--------------------------------->s
| |
e------->i--->u e---->t
| | | | |
a--->d d l--->y l o
| | | |
r l l c--->p
|
k
但是我意识到我的插入功能没有做同样的事情，因此当我试图找到这些单词时，我无法找到它们。
例如：当我搜索（熊，公牛，买入，卖出，停止）时，结果是FOUND，但是当我搜索（床，买入，卖出）时，结果没有找到。所有插入的字符串的预期结果应该是FOUND。
我在下面发布我的代码。期待一些帮助而不是完全代码，只是指向我出错的地方或我错过的地方。
/* I am trying to add few words in the tree using Tries Algorithm and
* then trying to find them */
#include <stdio.h>
#include <stdlib.h>
typedef struct node{
char info;
struct node *nextSibling;
struct node *child;
int count;
} node;
struct node* insert(struct node *ptr,char *string);
typedef enum Result {FALSE,TRUE} SEARCH;
SEARCH find(struct node *ptr,char *string);
void main()
{
struct node *headptr = NULL;
char string[256];
headptr = insert(headptr,"bear");
headptr = insert(headptr,"bed");
headptr = insert(headptr,"bid");
headptr = insert(headptr,"bull");
headptr = insert(headptr,"buy");
headptr = insert(headptr,"sell");
headptr = insert(headptr,"stock");
headptr = insert(headptr,"stop");
printf("bear bed bid bull buy sell stock stop\n");
printf("Enter a string to search:\n");
scanf("%s",string);
if(find(headptr,string)){
printf("Found\n");
}else{
printf("Not Found\n");
}
}
struct node* insert(struct node *ptr,char *string){
struct node *temp = NULL;
struct node *p = NULL;
char info = '\0';
if(!string[0])
return NULL;
info = string[0];
string++;
temp = (struct node *)malloc(sizeof(struct node));
temp->info = info;
temp->nextSibling = NULL;
temp->child = NULL;
temp->count = 1;
if((ptr == NULL)||(ptr->info > info)){
temp->nextSibling = ptr;
ptr = temp;
ptr->child = insert(ptr->child,string);
return ptr;
}
else{
p = ptr;
while(p->nextSibling){
if(p->info == info){
p->count += 1;
free(temp);
p->child = insert(p->child,string);
if ( ptr->nextSibling == p )
return ptr;
else
return p;
}
if((p->nextSibling)->info > info){
temp->nextSibling = p->nextSibling;
p->nextSibling = temp;
temp->child = insert(temp->child,string);
if ( ptr->nextSibling == p )
return ptr;
else
return p;
}
p = p->nextSibling;
}
if(!(p->nextSibling)){
if(p->info == info){
p->count += 1;
free(temp);
temp = NULL;
p->child = insert(p->child,string);
if ( ptr->nextSibling == p )
return ptr;
else
return p;
}
else{
temp->nextSibling = p->nextSibling;
p->nextSibling = temp;
temp->child = insert(temp->child,string);
if ( ptr->nextSibling == p )
return ptr;
else
return p;
}
}
}
}
SEARCH find(struct node *ptr,char *string){
char info = '\0';
struct node *p = NULL;
SEARCH rc = FALSE;
if(!string[0]){
rc = TRUE;
return rc;
}
info = string[0];
string++;
if(ptr == NULL){
rc = FALSE;
}
else{
p = ptr;
while(p){
if(p->info == info){
rc =find(p->child,string);
break;
}
else if(p->info > info){
if (!string[0])
rc = FALSE;
else
rc =find(p->child,string);
break;
}
else if ( p->info < info)
{
rc =find(p->child,string);
break;
}
p = p->nextSibling;
}
}
return rc;
}
答案 0 :(得分：1)
我认为我只是弄乱了插入函数中的返回地址，这相当于错误的结果。我也不知道在写find函数时我在想什么。
我在这里发布我的工作代码，但我对此并不满意，因为我认为它可以做得更好。
请评论：）
#include <stdio.h>
#include <stdlib.h>
typedef struct node{
char info;
struct node *nextSibling;
struct node *child;
int count;
} node;
struct node* insert(struct node *ptr,char *string);
void print(struct node *ptr);
typedef enum Result {FALSE,TRUE} SEARCH;
SEARCH find(struct node *ptr,char *string);
void main()
{
struct node *headptr = NULL;
char string[256];
headptr = insert(headptr,"bear");
headptr = insert(headptr,"bid");
headptr = insert(headptr,"bed");
headptr = insert(headptr,"bull");
headptr = insert(headptr,"buy");
headptr = insert(headptr,"sell");
headptr = insert(headptr,"stock");
headptr = insert(headptr,"stop");
printf("bear bed bid bull buy sell stock stop\n");
printf("Enter a string to search:\n");
scanf("%s",string);
if(find(headptr,string)){
printf("Found\n");
}else{
printf("Not Found\n");
}
}
struct node* insert(struct node *ptr,char *string){
struct node *temp = NULL;
struct node *p = NULL;
char info = '\0';
if(!string[0])
return NULL;
info = string[0];
string++;
temp = (struct node *)malloc(sizeof(struct node));
temp->info = info;
temp->nextSibling = NULL;
temp->child = NULL;
temp->count = 1;
if((ptr == NULL)||(ptr->info > info)){ /*Inserting 1st node or first node greater than the new node*/
temp->nextSibling = ptr;
ptr = temp;
temp->child = insert(temp->child,string);
return ptr;
}
else{
p = ptr;
while(p->nextSibling){
if(p->info == info){
p->count += 1;
free(temp);
p->child = insert(p->child,string);
return ptr;
}
if((p->nextSibling)->info > info){
temp->nextSibling = p->nextSibling;
p->nextSibling = temp;
temp->child = insert(temp->child,string);
return ptr;
}
p = p->nextSibling;
}
if(!(p->nextSibling)){
if(p->info == info){ /*1st node or last node equal to the new node*/
p->count += 1;
free(temp);
temp = NULL;
p->child = insert(p->child,string);
return ptr;
}
else{ /*New node is to be inserted at the end*/
temp->nextSibling = p->nextSibling;
p->nextSibling = temp;
temp->child = insert(temp->child,string);
return ptr;
}
}
}
}
SEARCH find(struct node *ptr,char *string){
char info = '\0';
struct node *p = NULL;
SEARCH rc = FALSE;
if(!string[0]){ /* End of string case */
rc = TRUE;
return rc;
}
if(ptr == NULL){
rc = FALSE;
}
else{
p = ptr;
while(p){
if(p->info == string[0]){/*Checking the first node for match*/
rc = find(p->child,++string);
return rc;
}
p = p->nextSibling;
}
}
return rc;
}