HDOJ 1536 SG函数的基本应用

从题意来看，是基本的SG函数应用，把刚学的set用进去优化，发现不行...

TLE...

再看看SG的原理，网上大部分都是采用递归，而那些题解报告都是一把抄，嗤之以鼻..

下面是直接TLE的代码：

/*********************
S-Nim
Sevenster
2012.08.26 12:55
*********************/
#include<iostream>
#include<algorithm>
#include<set>
using namespace std;

bool cmp( int a,int b ){ return a>b; }

void setSG( int *sg,int *S,int Sn )
{
 	 //sort( S,S+Sn,cmp );
 	 sg[0]=0;
 	 set<int> se;
 	 set<int>::iterator it;
 	 for( int i=1;i<=10000;i++ )
 	 {
	  	  se.erase(se.begin(),se.end());
	  	  for( int j=0;j<Sn;j++ )
	  	  {
		   	   if( i-S[j]<0 )
			   	   continue;
			   se.insert( sg[i-S[j]] );
  	   	  }
  	   	  int fnum=0;
  	   	  while( true )
  	   	  {
		   		 if( se.find(fnum)==se.end() )
		   		 {
		   		 	 sg[i]=fnum;
		   		 	 break;
		   		 }
		   		 fnum++;
	  	  }
	 }
 	 return ;
}

int main()
{
 	int S_size;
 	int S[111];int sg[11111];
 	while( scanf("%d",&S_size)!=EOF&&S_size )
 	{
	 	   for( int i=0;i<S_size;i++ )
	 	   		scanf( "%d",&S[i] );
	 	   setSG( sg,S,S_size );
	 	   int T,n,data;
	 	   scanf( "%d",&T );
	 	   while( T-- )
	 	   {
		   		  int xo=0;
		   		  scanf( "%d",&n );
		   		  for( int i=0;i<n;i++ )
		   		  {
		   		  	   scanf( "%d",&data );
		   		  	   xo^=sg[data];
			      }
      	  		  printf( "%c",xo?'W':'L' );
  		   }
  		   printf( "\n" );
  	}
 	return 0;
}

看来STL不能胡乱用=.=

悲催悲催...

/*********************
S-Nim
Sevenster
2012.08.26 12:55
*********************/
#include<iostream>
#include<algorithm>
#include<set>
using namespace std;

bool cmp( int a,int b ){ return a>b; }

void setSG( int *sg,int *S,int Sn )
{
 	 //sort( S,S+Sn,cmp );
 	 sg[0]=0;
 	 //set<int> se;
 	 //set<int>::iterator it;
 	 bool flag[111];
 	 for( int i=1;i<=10000;i++ )
 	 {
	  	  memset(flag,0,sizeof(flag));
		  for( int j=0;j<Sn;j++ )
	  	  {
		   	   if( i-S[j]<0 )
			   	   continue;
			   flag[sg[i-S[j]]]=1;
  	   	  }
  	   	  for( int j=0;j<=101;j++ )
  	   	  	   if( flag[j]==0 )
  	   	  	   {
  	   	  	   	   sg[i]=j;
  	   	  	   	   break;
			   }
	 }
 	 return ;
}

int main()
{
 	int S_size;
 	int S[111];int sg[11111];
 	while( scanf("%d",&S_size)!=EOF&&S_size )
 	{
	 	   for( int i=0;i<S_size;i++ )
	 	   		scanf( "%d",&S[i] );
	 	   setSG( sg,S,S_size );
	 	   int T,n,data;
	 	   scanf( "%d",&T );
	 	   while( T-- )
	 	   {
		   		  int xo=0;
		   		  scanf( "%d",&n );
		   		  for( int i=0;i<n;i++ )
		   		  {
		   		  	   scanf( "%d",&data );
		   		  	   xo^=sg[data];
			      }
      	  		  printf( "%c",xo?'W':'L' );
  		   }
  		   printf( "\n" );
  	}
 	return 0;
}