hdu--1251--字典树
赤裸裸的字典树...就来熟悉下字典树的 顺便注意下写的时候的各种小细节
1 #include <iostream> 2 #include <cstring> 3 using namespace std; 4 5 const int size = 26; 6 char str[size]; 7 typedef struct trie 8 { 9 trie* next[size]; 10 int cnt; 11 }; 12 trie* root; 13 14 void init() 15 { 16 root = new trie; 17 for( int i = 0 ; i<size ; i++ ) 18 root->next[i] = NULL; 19 } 20 21 void create( char* str ) 22 { 23 int len = strlen(str); 24 trie* p = root; 25 //trie* q; 26 for( int i = 0 ; i<len ; i++ ) 27 { 28 int id = str[i] - 'a'; 29 if( p->next[id] == NULL ) 30 { 31 //q = new trie; 32 p->next[id] = new trie; 33 p->next[id]->cnt = 1; 34 for( int j = 0 ; j<size ; j++ ) 35 { 36 p->next[id]->next[j] = NULL; 37 } 38 //p->next[id] = q; 39 } 40 else 41 { 42 p->next[id]->cnt ++; 43 } 44 p = p->next[id]; 45 } 46 } 47 48 int find( char* str ) 49 { 50 int len = strlen(str); 51 trie* p = root; 52 for( int i = 0 ; i<len ; i++ ) 53 { 54 int id = str[i] - 'a'; 55 p = p->next[id]; 56 if( p==NULL ) 57 { 58 return 0; 59 } 60 } 61 return p->cnt; 62 } 63 64 int main() 65 { 66 init(); 67 while( gets(str) && str[0]!='\0' ) 68 { 69 create( str ); 70 } 71 while( cin >> str ) 72 { 73 cout << find(str) << endl; 74 } 75 return 0; 76 }
注释的也是正确的... 当时写着来 验证自己想法的=-=
today:
if you can't fly then run
if you can't run then walk
if you can't walk then crawl
but wharever you do you have to keep moving forward
just follow your heart