Hat’s Words

http://acm.hdu.edu.cn/showproblem.php?pid=1247

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
char c[50010][110] ;
struct node
{
    int flag ;
    struct node *next[26] ;
};
struct node *creat()
{
    int i ;
    struct node *p ;
    p = (struct node*)malloc(sizeof(struct node));
    p->flag = 0 ;
    for(i=0; i<26; i++)
    p->next[i] = NULL ;
    return p;
}
void insert(struct node *head, char *s)
{
    int i ;
    struct node *p = head ;
    int len = strlen(s) ;
    for(i=0; i<len; i++)
    {
        int t = s[i] - 'a' ;
        if(p->next[t]==NULL)
        {
            p->next[t] = creat() ;
        }
        p = p->next[t] ;
    }
    p->flag = 1 ;
}
int judge(struct node *head, char *s)
{
    struct node *p = head ;
    for(; *s!='\0';)
    {
        int t = *s - 'a' ;
        if(p->next[t]==NULL)
        return 0 ;
        p = p->next[t] ;
        if(p->flag==1&&*(s+1)=='\0')
        return 1 ;
        s++ ;
    }
    return 0 ;
}
int search(struct node *head, char *s)
{
    struct node *p = head ;
    for(; *s!='\0';)
    {
        int t = *s - 'a' ;
        if(p->next[t]==NULL)
        return 0 ;
        p = p->next[t] ;
        if(p->flag==1&&judge(head, s+1))
        {
            return 1;
        }
        s++ ;
    }
    return 0 ;
}
int main()
{
   int i = 0, j ;
   struct node *head = creat() ;
   while(gets(c[i])!=NULL)
   {
       insert(head, c[i]) ;
       i++ ;
   }
   for(j=0; j<i; j++)
   {
       if(search(head,c[j]))
       puts(c[j]) ;
   }
   return 0 ;
}