百练 2797:最短前缀

http://bailian.openjudge.cn/practice/2797/

#include<iostream>
using namespace std;

struct trie{
	int count;
	trie *next[26];
	trie(){
		count=0;
		int i=0;
		for(i=0;i<26;i++){
			next[i]=NULL;
		}
	}
}root;
char word[1001][21];

void insert(char w[]){
	trie *r = &root;
	int i;
	for(i=0;w[i];i++){
		int t = w[i]-'a';
		if(r->next[t]==NULL){
			r->next[t] = new trie;
			r->next[t]->count = 1;
		}else if(r->next[t])
			r->next[t]->count++;
		r = r->next[t];
	}
}

void search(char w[]){
	trie *r = &root;
	if(r == NULL)
		return;
	int i;
	for(i=0;w[i];i++){
		int t = w[i]-'a';
		if(r->next[t]==NULL)
			return;
		cout<<w[i];
		if(r->next[t]->count==1)
			break;
		r = r->next[t];
	}
}

int main(){
	int i,n=1;
	while(cin>>word[n]){
		if(word[n][0]=='0')
			break;
		insert(word[n++]);
	}
	for(i=1;i<n;i++){
		cout<<word[i]<<" ";
		search(word[i]);
		cout<<endl;
	}
	return 0;
}