http://poj.org/problem?id=3630
import java.util.Scanner;
public class Main {
private static Trie trie = new Trie();
private static boolean isConsistent = true;
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int t = sc.nextInt();
for (int i = 0; i < t; ++i) {
int n = sc.nextInt();
sc.nextLine();
trie = new Trie();
isConsistent = true;
for (int j = 0; j < n; ++j) {
String phone = sc.nextLine();
if (isConsistent)
buildTrie(phone);
}
if (isConsistent)
System.out.println("YES");
else
System.out.println("NO");
}
}
static void buildTrie(String s) {
// char[] c = s.toCharArray();
int len = s.length();
Trie tmpTrie = trie;
for (int i = 0; i < len; ++i) {
int ch = Integer.parseInt(s.substring(i, i + 1));
// System.out.println(ch+"---"+(int)ch);
Trie tmp = tmpTrie.next[ch];
if (tmp == null) {
tmp = new Trie();
tmp.node = 1;
if (i == len - 1)
tmp.isDispear = true;// 表示这是一个电话的结尾
tmpTrie.next[ch] = tmp;
tmpTrie = tmp;
} else {
if (tmp.isDispear) {
isConsistent = false;
break;
}
if (i == len - 1) {
isConsistent = false;
break;
}
tmpTrie = tmp;
}
}
}
private static class Trie {
int node = 0;
boolean isDispear = false;//是否是某个电话号码的最后一个
Trie[] next = new Trie[10];
}
}
//出处:<a href="http://blog.csdn.net/lazy_p/archive/2010/06/21/5683414.aspx" target="_blank">http://blog.csdn.net/lazy_p/archive/2010/06/21/5683414.aspx</a>