数据结构 － trie

 #include <cstring>
 #include <iostream>
 #include <map>
 #include <cstdio>
 using namespace std;
 class Trie{
 private :
     map<char,Trie *> * root;
     pair<bool,int> info;
     inline Trie * makeNext(char c){
         if(root == NULL){
             root = new map<char ,Trie * >;
         }
         map<char, Trie *>::iterator it  = root->find(c);
         Trie * in ;
         if( it ==  root->end()){
             in = new Trie();
             root->insert( pair<char , Trie * >(c,in));
         }else{
             in = it->second;
         }
         info.second ++ ;
         return in;
     }
     inline void makeEnd(){
         info.second ++ ;
         info.first = true;
     }
     inline Trie * getChild(char c){
         //该节点后面什么都没有了
         if( root == NULL ){
             return NULL;
         }
         map<char, Trie *>::iterator it  = root->find(c);
         if(it == root->end()){
             //有兄弟节点，但是没有这个后续
             return NULL;
         }
         return it->second;
     }
     void destory(){
         if(root != NULL){
             for(map<char ,Trie *> :: iterator it = root->begin() ; it!=root->end() ; ++ it ){
                 it->second->destory();
             }
             delete root;
         }
     }
 public :
     static pair<bool,int> None ;
     Trie(){
         root = NULL;
         info = pair<bool,int>(false,);
     }
     ~Trie(){
         destory();
     }
     void addStr(char * str){
         int len = strlen(str);
         Trie * nowRoot = this;
         while( (*str)!='\0'){
             nowRoot = nowRoot->makeNext(*str);
             ++str;
         }
         nowRoot->makeEnd();
     }

     pair<bool,int> findStr(char * str){
         Trie * nowRoot = this;
         while((*str)!='\0'){
             nowRoot = nowRoot->getChild(*str);
             if( nowRoot == NULL){
                 return None;
             }
             str++;
         }
         return nowRoot -> info;
     }
 };
 pair<bool,int> Trie :: None = pair<bool,int>(false,-);
 int main(){
     Trie * a = new Trie();
     a->addStr("abcdfg");
     a->addStr("abcd");
     a->addStr("abc");
     a->addStr("ab");
     cout<<"stop "<<endl;
     pair <bool,int> ans = a->findStr("abc");
     cout<< ans.first << " " << ans.second<<endl;
     delete a;
     return ;
 }