HDU1671用指针实现的字典树

来源：互联网发布：电信运营商数据编辑：程序博客网时间：2024/04/30 13:31

用指针传递字典树，时空效率更高
用字符串代替字符数组，更方便

#include <iostream>#include <string>#include <algorithm>using namespace std;string str[10005];struct dictree{struct dictree *child[10];int n;dictree(){ memset(child,0,sizeof(child));n=0;}};bool insert(dictree* root,string s){int len,i,j;struct dictree *current,*newnode;len=s.length();if(len==0)return 0;current=root;for(i=0;i<len;i++){if(current->n == 1)return 1;if(current->child[s[i]-'0']!=0)current=current->child[s[i]-'0'];else{newnode=(struct dictree *)malloc(sizeof(struct dictree));for(j=0;j<10;j++)newnode->child[j]=0;current->child[s[i]-'0']=newnode;current=newnode;current->n=0;}if(i == len - 1)current->n=1;}return 0;}bool cmp(string s1, string s2){return s1.length() < s2.length();}void clear(dictree* root){if(root == NULL)return;for(int i = 0; i < 10; i++)clear(root->child[i]);delete root;}int main(){int t, n, i;cin>>t;while(t--){dictree *root = new dictree;bool flag = 0;cin>>n;for(i = 0; i < n; i++)cin>>str[i];sort(str, str+n, cmp);for(i = 0; i < n; i++){if(insert(root, str[i])){flag = 1;break;}}if(flag == 1)cout<<"NO"<<endl;elsecout<<"YES"<<endl;clear(root);}return 0;}