建立一个单链表，要求实现以下功能：查找元素为X的节点，求单链表的长度，插入一个元素值为X的结点，删除元素值为X的结点！！！！

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct _node{
    int val;
    char name[20];
    struct _node *next;
}node;

void insertnode(node **head, int data, char *name)
{
    node *tmp;
    node *p = (node *)malloc(sizeof(node));
    p->val = data;
    strcpy(p->name, name);
    p->next = *head;
    *head = p;
}

node *findnode(node *head, int key)
{
    while(head)
    {
        if (head->val == key)
        {
            return head;
        }
        head = head->next;
    }
    return NULL;
}
int getnodelen(node *head)
{                                                                                                                 
    int ret = 0;                                                                                                  
    while(head)                                                                                                   
    {                                                                                                            
        ret ++;                                                                                                   
        head = head->next;                                                                                       
    }                                                                                                            
    return ret;                                                                                                   
}         
int deletenode(node **head, int data)                                                                             
{                                                                                                                 
    node *cur = *head, *pre = *head;                                                                              
    while(cur)                                                                                                   
    {                                                                                                            
        if (cur->val == data)                                                                                    
        {                                                                                                         
            if(cur == *head)                                                                                      
            {                                                                                                     
                *head = cur->next;                                                                                
            }else                                                                                                
            {                                                                                                     
                pre->next = cur->next;                                                                           
            }                                                                                                     
            free(cur);                                                                                            
            printf("delet successful!\n");                                                                        
            return 1;                                                                                             
        }                                                                                                         
        pre = cur;                                                                                                
        cur = cur->next;                                                                                          
    }                                                                                                            
    printf("didn't node, delet faile!\n");                                                                        
    return 0;                                                                                                     
}                     
void deleteall(node *head)                                                                                       
{                                                                                                                 
    node *p;                                                                                                      
    while(head)                                                                                                   
    {                                                                                                            
        p = head->next;                                                                                          
        free(head);                                                                                               
        head = p;                                                                                                
    }                                                                                                            
}                                                                                                                 
void print(node *head)                                                                                            
{                                                                                                                 
    while(head)                                                                                                   
    {                                                                                                            
        printf("name : %s val : %d\n", head->name, head->val);                                                   
        head = head->next;                                                                                       
    }                                                                                                            
}                 
int main(void)                                                                                                   
{                                                                                                                 
    int cnt, val;                                                                                                      
    char name[20];                                                                                                
    node *head = NULL, *p;                                                                                       
                                                                                                                  
    while(scanf("%d", &val) == 1)                                                                                 
    {                                                                                                            
        scanf("%s", name);                                                                                       
        insertnode(&head, val, name);                                                                             
    }                                                                                                            
    while(getchar() != '\n');                                                                                    
    cnt = getnodelen(head);                                                                                       
    printf("cnt = %d\n", cnt);                                                                                    
                                                                                                                  
    printf("input elem val : ");                                                                                 
    scanf("%d", &val);                                                                                            
    if ((p = findnode(head, val)) != NULL)                                                                        
    {                                                                                                            
        printf("name : %s\n", p->name);                                                                           
    }                                                                                                            
    printf("input delete elem val : ");                                                                           
    scanf("%d", &val);                                                                                            
                                                                                                                  
    printf("before delete : \n");                                                                                 
    print(head);                                                                                                  
    deletenode(&head, val);                                                                                       
                                                                                                                  
    printf("after delete : \n");                                                                                 
    print(head);                                                                                                  
    deleteall(head);                                                                                             
}   
小写了一下，测一下吧，希望对你有帮助~~~囧。。。好像又有种帮人做作业的感觉呀。。。汗