FAFU 1557
构建字典序，模拟二叉树建26叉树
1 #include <stdio.h> 2 #include <string.h> 3 #include <stdlib.h> 4 #include <math.h> 5 #include <time.h> 6 #include <ctype.h> 7 #include <string> 8 #include <queue> 9 #include <set> 10 #include <map> 11 #include <stack> 12 #include <vector> 13 #include <algorithm> 14 #include <iostream> 15 #define PI acos( -1.0 ) 16 using namespace std; 17 typedef long long ll; 18 19 const int NO = 1e5 + 5; 20 char ch[NO]; 21 int n; 22 struct ND 23 { 24 int win; 25 ND *next[26]; 26 }; 27 28 int Solve( ND *tree ) 29 { 30 for( int i = 0; i < 26; ++i ) 31 { 32 if( tree->next[i] == NULL ) continue; 33 if( Solve( tree->next[i] ) ) 34 { 35 tree->win = 0; 36 return 0; 37 } 38 } 39 tree->win = 1; 40 return 1; 41 } 42 43 int main() 44 { 45 int T; 46 scanf( "%d", &T ); 47 while( T-- ) 48 { 49 ND *tree; 50 tree = new ND; 51 for( int i = 0; i < 26; ++i ) 52 tree->next[i] = NULL; 53 scanf( "%d", &n ); 54 for( int i = 0; i < n; ++i ) 55 { 56 scanf( "%s", ch ); 57 ND *p = tree; 58 int len = strlen( ch ); 59 for( int j = 0; j < len; ++j ) 60 { 61 int cur = ch[j] - 'a'; 62 if( p->next[cur] == NULL ) 63 { 64 p->next[cur] = new ND; 65 p = p->next[cur]; 66 p->win = 0; 67 for( int t = 0; t < 26; ++t ) 68 p->next[t] = NULL; 69 } 70 else p = p->next[cur]; 71 } 72 } 73 if( !Solve( tree ) ) puts( "First." ); 74 else puts( "Second." ); 75 } 76 return 0; 77 }
