ZOJ 2859 二维RMQ

// =====================================================================================
// 
//       Filename:  zoj2859.cpp
// 
//    Description:  2D RMQ -- Orz...卡了输出...
// 
//        Version:  1.0
//        Created:  2012年03月02日 22时17分57秒
//       Revision:  none
//       Compiler:  g++
// 
//         Author:  SphinX (Whisper), [email protected]
//        Company:  HFUT
// 
// =====================================================================================

#include 
#include 
#include 
using namespace std;

const int MAXN = 302;
const int MAXK = 9;

int test, n, m;
int mtx[MAXN][MAXN], dp[MAXN][MAXN][MAXK][MAXK];
int pow_hash[MAXK], log_hash[MAXN];

void preproces()
{
	log_hash[0] = 0;
	log_hash[1] = 0;
	for (int ind = 2, k = 1; ind < MAXN; ++ind)
	{
		if ((1 << (k + 1)) <= ind)
		{
			++k;
		}
		log_hash[ind] = k;
	}
	for (int k = 0; (1 << k) < MAXN; ++k)
	{
		pow_hash[k] = (1 << k);
	}
	return ;
}
void initRMQ()
{
	int k = log_hash[n];
	for (int row = 0; row < n; ++row)
	{
		for (int col = 0; col < n; ++col)
		{
			dp[row][col][0][0] = mtx[row][col];
		}
	}
	for (int i = 0; i <= k; ++i)
	{
		for (int j = 0; j <= k; ++j)
		{
			if (0 == i && 0 == j)
			{
				continue ;
			}
			for (int row = 0; row + pow_hash[i] <= n; ++row)
			{
				for (int col = 0; col + pow_hash[j] <= n; ++col)
				{
					if (0 == i)
					{
						dp[row][col][i][j] = 
							min(dp[row][col][i][j - 1], dp[row][col + pow_hash[j - 1]][i][j - 1]);
					}
					else
					{
						dp[row][col][i][j] = 
							min(dp[row][col][i - 1][j], dp[row + pow_hash[i - 1]][col][i - 1][j]);
					}
				}
			}
		}
	}
	return ;
}
int queryRMQ(int r1, int c1, int r2, int c2)
{
	int kr = log_hash[r2 - r1 + 1];
	int kc = log_hash[c2 - c1 + 1];
	return min(
			min(dp[r1][c1][kr][kc], dp[r2 - pow_hash[kr] + 1][c2 - pow_hash[kc] + 1][kr][kc]), 
			min(dp[r2 - pow_hash[kr] + 1][c1][kr][kc], dp[r1][c2 - pow_hash[kc] + 1][kr][kc])
			);
}
void ace()
{
	int cas = 1;
	int r1, c1, r2, c2;
	preproces();
	for (scanf("%d", &test); test--; ++cas)
	{
		scanf("%d", &n);
		for (int i = 0; i < n; ++i)
		{
			for (int j = 0; j < n; ++j)
			{
				scanf("%d", &mtx[i][j]);
			}
		}
		initRMQ();
		scanf("%d", &m);
		while (m--)
		{
			scanf("%d %d %d %d", &r1, &c1, &r2, &c2);
			printf("%d\n", queryRMQ(r1 - 1, c1 - 1, r2 - 1, c2 - 1));
		}
	}
	return ;
}
int main(int argc, char *argv[])
{
	ace();
	return EXIT_SUCCESS;
}