hdu1305之字典树

#include<iostream>#include<cstdio>#include<cstdlib>#include<cstring>#include<string>#include<queue>#include<algorithm>#include<map>#include<iomanip>using namespace std;const int MAX=2;bool flag;struct TrieNode{bool mark;//标记一个单词 TrieNode *next[MAX];TrieNode(){mark=false;memset(next,0,sizeof next);}}root;void InsertNode(char *a){int k=0;TrieNode *p=&root;while(a[k]){if(!p->next[a[k]-'0'])p->next[a[k]-'0']=new TrieNode;else if(!a[k+1])flag=false;//a是其他字符串的字串 p=p->next[a[k++]-'0'];if(p->mark)flag=false;//其他字符串是a的字串 } p->mark=true;}void Free(TrieNode *p){for(int i=0;i<2;++i){if(p->next[i])Free(p->next[i]); }delete p;} int main(){char s[10];int num=0;while(cin>>s){flag=true;while(s[0] != '9'){if(flag)InsertNode(s);cin>>s;}if(flag)cout<<"Set "<<++num<<" is immediately decodable"<<endl;else cout<<"Set "<<++num<<" is not immediately decodable"<<endl;for(int i=0;i<2;++i)if(root.next[i])Free(root.next[i]); //Free(&root);//清空本次的字符串(节点)root.next[0]=root.next[1]=NULL;}return 0;}