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Phone List

时间限制：1000 ms  |  内存限制：65535 KB

难度：4

描述

Given a list of phone numbers, determine if it is consistent in the sense that no number is the prefix of another. Let's say the phone catalogue listed these numbers:

• Emergency 911
• Alice 97 625 999
• Bob 91 12 54 26

In this case, it's not possible to call Bob, because the central would direct your call to the emergency line as soon as you had dialled the first three digits of Bob's phone number. So this list would not be consistent.

输入

The first line of input gives a single integer, 1 ≤ t ≤ 10, the number of test cases. Each test case starts with n, the number of phone numbers, on a separate line, 1 ≤ n ≤ 100000. Then follows n lines with one unique phone number on each line. A phone number is a sequence of at most ten digits.

输出

For each test case, output "YES" if the list is consistent, or "NO" otherwise.

#include<iostream>#include<algorithm>#include<cstring>#include<string.h>#include<assert.h>#include<stdio.h>#include<stdlib.h>#include<vector>#include<cstring>#include<iomanip>#include<iterator>using namespace std;const int Max=10;typedef struct trie{int v;trie* next[Max];}trie;trie *root;void createtrie(char *str){int len=strlen(str);trie*p=root,*q;for(int i=0;i<len;i++){int id=str[i]-'0';if(p->next[id]==NULL){q=(trie*)malloc(sizeof(trie));q->v=1;for(int j=0;j<Max;j++){q->next[j]=NULL;}p->next[id]=q;p=p->next[id];}else{p->next[id]->v++;p=p->next[id];}}p->v=-1;//如果p为结尾的话则v的值为-1;}int findtrie(char *str){int len=strlen(str);trie* p=root;for(int i=0;i<len;i++){int id=str[i]-'0';p=p->next[id];if(p==NULL){return 0;}if(p->v==-1){return -1;//若此字符创已经是要查找的此串则结束查找；}}return -1;//查找到最好则此串已经是某个字符串的子串;}int  deletetire(trie *t){int i;if(t==NULL){return 0;}for(int i=0;i<Max;i++){//t=t->next[i];if(t->next[i]!=NULL){deletetire(t->next[i]);}}free(t);return 0;}int main(){char str[20];int n;scanf("%d",&n);while(n--){int num,flag;scanf("%d",&num);flag=0;root = (trie *) malloc (sizeof(trie));for(int i=0;i<Max;i++){root->next[i]=NULL;}for(int i=0;i<num;i++){scanf("%s",str);if(findtrie(str)==-1){flag=1;}if(flag){continue;}createtrie(str);}if(flag){printf("NO\n");}elseprintf("YES\n");deletetire(root);}return 0;}

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