（字典树）HDU - 1247 Hat’s Words

  1 #include <set>
  2 #include <map>
  3 #include <list>
  4 #include <cmath>
  5 #include <queue>
  6 #include <vector>
  7 #include <bitset>
  8 #include <string>
  9 #include <cctype>
 10 #include <cstdio>
 11 #include <cstring>
 12 #include <cstdlib>
 13 #include <iostream>
 14 #include <algorithm>
 15 
 16 using namespace std;
 17 
 18 typedef long long ll;
 19 typedef unsigned long long ull;
 20 #define inf (0x3f3f3f3f)
 21 #define lnf (0x3f3f3f3f3f3f3f3f)
 22 #define eps (1e-8)
 23 int sgn(double a){return a < -eps ? -1 : a < eps ? 0 : 1;}
 24 
 25 //--------------------------
 26 
 27 struct  Trie_node {
 28     int cnt;
 29     int next[26];
 30     bool exist;
 31 }tree[400010];
 32 int nxt;
 33 
 34 int  createTrieNode() {
 35     memset(&tree[nxt], 0, sizeof(Trie_node));
 36     return nxt++;
 37 }
 38 
 39 void Trie_insert(string &word) {
 40     int rt=0;
 41     int len=word.length();
 42     for(int i=0;i<len;i++){
 43         int id = word[i]-‘a‘;
 44         if(!tree[rt].next[id]){
 45             tree[rt].next[id]=createTrieNode();
 46         }
 47         rt=tree[rt].next[id];
 48         tree[rt].cnt++;
 49     }
 50     tree[rt].exist=true;
 51 }
 52 
 53 bool Trie_search2(string word){
 54     int rt=0;
 55     int len=word.length();
 56     for(int i=0;i<len;i++){
 57         int id=word[i]-‘a‘;
 58         if(!tree[rt].next[id])return false;
 59         rt=tree[rt].next[id];
 60     }
 61     return tree[rt].exist;
 62 }
 63 
 64 bool Trie_search1(string &word) {
 65     int rt=0;
 66     int len=word.length();
 67     int res=0;
 68     for(int i=0;i<len;i++){
 69         int id=word[i]-‘a‘;
 70         rt=tree[rt].next[id];
 71         if(tree[rt].exist&&Trie_search2(word.substr(i+1,len-i-1)))res++;
 72     }
 73     return res>0;
 74 }
 75 
 76 void init(){
 77     nxt=1;
 78     memset(&tree[0],0,sizeof(Trie_node));
 79 }
 80 
 81 string word[50010];
 82 
 83 void solve() {
 84     init();
 85     int n=0;
 86     while(cin>>word[n]){
 87         Trie_insert(word[n]);
 88         n++;
 89     }
 90     for(int i=0;i<n;i++){
 91         if(Trie_search1(word[i]))cout<<word[i]<<endl;
 92     }
 93 
 94 }
 95 
 96 
 97 
 98 
 99 int main() {
100 
101 #ifndef ONLINE_JUDGE
102     freopen("in.txt", "r", stdin);
103     //freopen("out.txt", "w", stdout);
104 #endif
105     //iostream::sync_with_stdio(false);
106     solve();
107     return 0;
108 }