poj 2019 Cornfields

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#include<iostream>

#include<cstdio>

#include<cstdlib>

#include<algorithm>

#include<cmath>

#include<queue>

#include<set>

#include<cstring>

#include<vector>

#include<string>

#define LL long long

using namespace std;

class Node

{

public:

    int l,r,max,min;    

};

class Tree

{

public:

      int l,r;

      Node n[1024];

}T[1024];

int Max,Min;

int map[254][254];

void build_y( Node *p ,int l , int r , int cnt , int s,int e )

{

//     printf( "l==%d r==%d\n",l,r );

     p[cnt].l = l ;p[cnt].r = r;

     if( l == r ) 

     {

         int MAX = -1,MIN = 0x7fffffff;

         for( int i = s ; i <= e ; i ++ )

         {

              MAX = max( MAX , map[i][l] );

              MIN = min( MIN , map[i][l] );        

         }

         p[cnt].min = MIN ;p[cnt].max = MAX;

         return;

     }    

     int mid = ( l + r )>>1;

     build_y( p , l , mid ,cnt*2,s,e );

     build_y( p , mid + 1 , r , cnt*2+1,s,e );

     p[cnt].max = max( p[cnt*2].max , p[cnt*2+1].max );

     p[cnt].min = min( p[cnt*2].min , p[cnt*2+1].min );

//     printf( "%d %d %d %d\n",l,r,p[cnt].max , p[cnt].min );

}

void build( int l, int r , int cnt , int N )

{

     T[cnt].l = l ; T[cnt].r = r;

     build_y( T[cnt].n ,1 , N , 1 ,l ,r );

     if( l == r ) return;

     int mid = ( l + r )>>1;

     build( l , mid , cnt*2 , N );

     build( mid + 1 , r , cnt*2+1 , N );    

}

void Query_y( Node *p ,int l, int r , int cnt )

{

//    printf( "af" );

     if( l <= p[cnt].l && r >= p[cnt].r )

     {

         Max = max( Max , p[cnt].max );

         Min = min( Min , p[cnt].min );

         return;        

     }    

     int mid = ( p[cnt].l + p[cnt].r )>>1;

     if( mid >= r ) Query_y( p , l ,r ,cnt*2 );

     else if( mid < l ) Query_y( p , l , r , cnt* 2 + 1 );

     else

     {

         Query_y( p , l , mid , cnt*2 );

         Query_y( p , mid + 1, r , cnt*2 + 1 );        

     }

}

void Query( int l , int r , int cnt ,int y1 , int y2 )

{

//    printf( "%d %d %d %d %d\n",l,r,cnt,T[cnt].l,T[cnt].r );

     if( l<=T[cnt].l&&r >= T[cnt].r )

     {//printf( "af" );

         Query_y( T[cnt].n ,y1, y2 ,1 );

         return ;        

     }

     int mid = ( T[cnt].l + T[cnt].r )>>1;

     if( mid >= r ) Query( l , r , cnt*2 , y1 , y2 );

     else if( mid < l ) Query( l , r, cnt * 2 + 1, y1, y2 );

     else

     {

          Query( l , mid , cnt*2 , y1 ,y2 );

          Query( mid + 1 , r , cnt*2 +1 , y1 , y2 );        

     }

}

int main(  )

{

    int N,B,K,R,L;

    while( scanf( "%d %d %d",&N,&B,&K )==3 )

    {

        for( int i = 1; i <= N; i ++ )

           for( int j = 1 ; j <= N; j ++ )

                 scanf( "%d",&map[i][j] );

        build( 1 , N ,1 ,N );

        for( int i = 0 ; i < K ; i++ )

        {

            Max = -1 ; Min = 0x7ffffff;

            scanf( "%d %d",&R,&L );

            Query( R , R + B -1, 1 , L , L + B-1 );

//            printf( "%d %d\n",Max ,Min );

            printf( "%d\n",Max - Min );

        }     

    }

    //system( "pause" );

    return 0;

}