poj 3630 Phone List

原题链接：http://poj.org/problem?id=3630

字典树的简单应用，具体实现如下：

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
typedef char State[12];
typedef struct _trie{
	int cnt;
	struct _trie *next[10];
}trie, *Trie;
State st[10002];
trie node[1000000];
int sz = 0;
Trie built(){
	Trie T = &node[sz++];
	memset(T, 0, sizeof(trie));
	return T;
}
void insert(Trie T, char *src){
	char *p = src;
	while (*p != '\0'){
		if (T->next[*p - '0'] == NULL) T->next[*p - '0'] = built();
		T = T->next[*p - '0'];
		T->cnt++;
		p++;
	}
}
int search(Trie T, char *src){
	char *p = src;
	while (*p != '\0'){
		if (T == NULL || T->next[*p - '0'] == NULL) return 0;
		T = T->next[*p - '0'];
		p++;
	}
	return T->cnt;
}
int main(){
#ifdef LOCAL
	freopen("in.txt", "r", stdin);
	freopen("out.txt", "w+", stdout);
#endif
	int t, n;
	State rev;
	scanf("%d", &t);
	while (t--){
		sz = 0;
		scanf("%d", &n);
		Trie root = built();
		int k = n, count = 0, flag = 0;
		while (k--){
			scanf("%s", rev);
			strcpy(st[count++], rev);
			insert(root, rev);
		}
		for (k = 0; k < n; k++){
			if (search(root, st[k]) > 1){
				printf("NO\n");
				flag = 1;
				break;
			}
		}
		if(!flag) printf("YES\n");
	}
	return 0;
}