Phone List

Time Limit: 3000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 10837 Accepted Submission(s): 3735

Problem Description

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: 1. Emergency 911 2. Alice 97 625 999 3. 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.

Input

The first line of input gives a single integer, 1 <= t <= 40, the number of test cases. Each test case starts with n, the number of phone numbers, on a separate line, 1 <= n <= 10000. Then follows n lines with one unique phone number on each line. A phone number is a sequence of at most ten digits.

Output

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

Sample Input

2 3 911 97625999 91125426 5 113 12340 123440 12345 98346

Sample Output

NO YES

Source

2008 “Insigma International Cup” Zhejiang Collegiate Programming Contest - Warm Up（3）

简单字典树：

代码：实现 insert ,query,delete 三部分

 1 /*hdu 1671 ×ÖµäÊ÷*/
 2 #define LOCAL
 3 #include<cstdio>
 4 #include<cstring>
 5 #include<iostream>
 6 using namespace std;
 7 struct Trie
 8 {
 9    struct Trie *next[10];
10    bool tail;
11 };
12 char str[10005][12];
13 void in_Trie(char *s,Trie *root)
14 {
15    Trie *cur=root,*newcur;
16   for(int i=0;s[i]!='';i++)
17   {
18        if(cur->next[s[i]-'0']==NULL)
19      {
20          newcur=new Trie;   //(Trie*)malloc(sizeof(sizeof(Trie)));
21          for(int j=0;j<=9;j++)
22            newcur->next[j]=NULL;
23             newcur->tail=0;
24         cur->next[s[i]-'0']=newcur;
25      }
26     cur=cur->next[s[i]-'0'];
27   }
28    cur->tail=1;
29 }
30 bool query(char *s,Trie *root)
31 {
32     int i=0;
33     Trie *cur=root;
34     for(i=0;s[i];i++){
35        if(cur->tail==0&&cur->next[s[i]-'0']!=NULL)
36            cur=cur->next[s[i]-'0'];
37       else break;
38     }
39  if(s[i]!='') return 1;
40    return 0;
41 }
42 void dele(Trie *root)
43 {
44   for(int i=0 ; i<=9 ; i++ )
45       if(root->next[i]!=NULL)
46       dele(root->next[i]);
47  // free(root);
48  delete root;
49 }
50 int main()
51 {
52   #ifdef LOCAL
53   freopen("test.in","r",stdin);
54   #endif
55   int t,i,n;
56   Trie *root;
57   scanf("%d",&t);
58   while(t--)
59   {
60        root = new Trie ;
61        for(int j=0;j<=9;j++)
62        root->next[j]=NULL;
63        root->tail=0;
64 
65      scanf("%d",&n);
66     for(i=0;i<n;i++){
67       scanf("%s",str[i]);
68       in_Trie(str[i],root);
69     }
70 
71     for(i=0;i<n;i++)
72       if(query(str[i],root)!=0)
73         break;
74       dele(root);
75       if(i>=n)
76         printf("YESn");
77       else
78         printf("NOn");
79   }
80    return 0;
81 }

hdu----(1671)Phone List(Trie带标签)

Phone List