A hat’s word is a word in the dictionary that is the concatenation of exactly two other words in the dictionary.
You are to find all the hat’s words in a dictionary.

Standard input consists of a number of lowercase words, one per line, in alphabetical order. There will be no more than 50,000 words.
Only one case.

Your output should contain all the hat’s words, one per line, in alphabetical order.

a
ahat
hat
hatword
hziee
word

ahat
hatword
<code>

#include<iostream>
#include<string.h>
#include<stdlib.h>
#include<stdio.h>
using namespace std;
char str[50005][100],str1[100],str2[100];
struct dirtree 
{
   struct dirtree *child[26];
   bool hash;
};
struct dirtree *root;
void Insert(char*source)
{
     int i,j,len;
     len=strlen(source);
     if(len==0)return ;
     struct dirtree *current,*newnode;
     current=root;
     for(i=0;i<len;i++)
     {
        if(current->child[source[i]-'a']!=0)
        {
           current=current->child[source[i]-'a'];
           if(i==len-1)
           {
              current->hash=true;
              break;
           }
           
        }
        else
        {
           newnode=(struct dirtree*)malloc(sizeof(struct dirtree));
           for(j=0;j<26;j++)
           {
              newnode->child[j]=0;
              newnode->hash=false;
           }
           current->child[source[i]-'a']=newnode;
           current=newnode;
           if(i==len-1)
           {
              current->hash=true;
              break;
           }
            
        }
     }
}
bool Find(char *source)
{
    struct dirtree *current;
    int len=strlen(source);
    if(len==0)return 0;
    current=root;
    for(int i=0;i<len;i++)
    {
       if(current->child[source[i]-'a']!=0)
          current=current->child[source[i]-'a'];
       else
          return false;
    }
    return current->hash;
}
int main()
{
 
   int len = 0;
   int i, j, k, len1;
   root = (struct dirtree *)malloc(sizeof(struct dirtree));
   for(i = 0; i < 26; i++)
   {
      root->child[i] = 0;
      root->hash = false;
   }
   while(scanf("%s",str[len])!=EOF)
   {
       Insert(str[len]);
       len++;
   }
   for(i=0;i<len;i++)
   {
     len1=strlen(str[i]);
     for(j=1;j<len1;j++)
     {
        for(k=0;k<j;k++)
        {
           str1[k]=str[i][k];
        }
        str1[k]='/0';
        int t=0;
        for(k=j;k<len1;k++)
        {
           str2[t++]=str[i][k];
        }
        str2[t]='/0';
        if(Find(str1)&&Find(str2))
        {
           printf("%s/n",str[i]);
           break;
        }
     }
   } 
   //system("pause");
   return 0;
   
}