我决定用 C 语言编写一个程序,该程序将接受用户输入并使用哈希表执行操作...好吧,我遇到了障碍,我完全不知道发生了什么。当我运行我的代码时,一切都很好,直到我给出输入,然后我收到段错误。有没有人可以指出我的错误?当用户输入时,程序将根据 ascii 中的字母总数来决定将单词放在哪里。一旦我解决了这个问题,我就会将其添加进去,这样如果发生碰撞,它就会增加类似 7 的值,直到它找到一个可以去的地方。
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
struct hash *hashTable = NULL;
int eleCount = 0;
struct node {
int key;
char name[1024];
struct node *next;
};
struct hash {
struct node *head;
int count;
};
struct node * createNode(int key, char *name) {
struct node *newnode;
newnode = (struct node *)malloc(sizeof(struct node));
newnode->key = key;
strcpy(newnode->name, name);
newnode->next = NULL;
return newnode;
}
void insertToHash(int key, char *name) {
int hashIndex = key % eleCount;
struct node *newnode = createNode(key, name);
if (!hashTable[hashIndex].head) {
hashTable[hashIndex].head = newnode;
hashTable[hashIndex].count = 1;
return;
}
newnode->next = (hashTable[hashIndex].head);
hashTable[hashIndex].head = newnode;
hashTable[hashIndex].count++;
return;
}
void deleteFromHash(int key) {
int hashIndex = key % eleCount, flag = 0;
struct node *temp, *myNode;
myNode = hashTable[hashIndex].head;
if (!myNode) {
printf("Word not in hash Table!!\n");
return;
}
temp = myNode;
while (myNode != NULL) {
if (myNode->key == key) {
flag = 1;
if (myNode == hashTable[hashIndex].head)
hashTable[hashIndex].head = myNode->next;
else
temp->next = myNode->next;
hashTable[hashIndex].count--;
free(myNode);
break;
}
temp = myNode;
myNode = myNode->next;
}
if (flag)
printf("Word deleted from Hash Table by the power of Grey Skull\n");
else
printf("Word is not present in hash Table!\n");
return;
}
void searchInHash(int key) {
int hashIndex = key % eleCount, flag = 0;
struct node *myNode;
myNode = hashTable[hashIndex].head;
if (!myNode) {
printf("Searched word not in hash table\n");
return;
}
while (myNode != NULL) {
if (myNode->key == key) {
printf("Key : %d\n", myNode->key);
printf("Name : %s\n", myNode->name);
flag = 1;
break;
}
myNode = myNode->next;
}
if (!flag)
printf("Searched word not in hash table\n");
return;
}
void display() {
struct node *myNode;
int i;
for (i = 0; i < eleCount; i++) {
if (hashTable[i].count == 0)
continue;
myNode = hashTable[i].head;
if (!myNode)
continue;
printf("Key Word\n");
printf("----------------\n");
while (myNode != NULL) {
printf("%-12d", myNode->key);
printf("%-15s", myNode->name);
myNode = myNode->next;
}
}
return;
}
int main() {
int n, ch, key, i;
char name[1024],cas[5];
eleCount = 23;
hashTable = (struct hash *)calloc(n, sizeof (struct hash));
while (1) {
printf("\nword: Insert word\n#d: word Delete word\n");
printf("#s word: Search for word\n#p: Display hash table\n#Q: Exit\n");
printf("Enter your choice:");
fgets(name, 1023, stdin);
if(sscanf(name,"#d",&cas)==1)
{//delete
i=2;
while(name[i]!='\0')
{key=key+i;
i++;}
deleteFromHash(key);
}
else if(sscanf(name,"#s",&cas)==1)
{//search
i=2;
while(name[i]!='\0')
{key=key+i;
i++;}
searchInHash(key);
}
else if(sscanf(name,"#p",&cas)==1)
{//print
display();
}
else if(sscanf(name,"#Q",&cas)==1)
{//Quit
exit(0);
}
else
{//insert
while(name[i]!='\0')
{key=key+i;
i++;}
name[strlen(name) - 1] = '\0';
insertToHash(key, name);
}
}
return 0;
}
最佳答案
这里
hashTable = (struct hash *)calloc(n, sizeof (struct hash));
您正在调用calloc
,但从未初始化n
;变量 key
也没有初始化。
关于c - 哈希函数中的段错误(C),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/28363406/