[실4] 1018 - 체스판 다시 칠하기

#pragma region 라이브러리

#include <iostream>
//#include <format>
#include <cmath>
#include <functional>
#include <vector>
#include <map>
#include <stack>
#include <queue>
#include <deque>

using namespace std;

#pragma endregion

#pragma region 최적화용

#define FAST_IO() ios::sync_with_stdio(0); cin.tie(0);
#define y first
#define x second
#define INIT 9876543210
#define MAX_SIZE 8

using IntPair = pair<int, int>;
using DoubleVec = vector<vector<int>>;
using Vec = vector<int>;

// 상하좌우
IntPair dir[]
{
	{ 1, 0 },
	{-1, 0 },
	{ 0, -1 },
	{ 0, 1 }
};

#pragma endregion

// 화이트
string wb[]
{
	"WBWBWBWB",
	"BWBWBWBW",
	"WBWBWBWB",
	"BWBWBWBW",
	"WBWBWBWB",
	"BWBWBWBW",
	"WBWBWBWB",
	"BWBWBWBW"
};

// 블랙
string bb[]
{
	"BWBWBWBW",
	"WBWBWBWB",
	"BWBWBWBW",
	"WBWBWBWB",
	"BWBWBWBW",
	"WBWBWBWB",
	"BWBWBWBW",
	"WBWBWBWB"
};

vector<string> board;

int GetCnt(int y, int x, int type = 0)
{
	int cnt = 0;

	for (int i = 0; i < MAX_SIZE; i++)
	{
		for (int j = 0; j < MAX_SIZE; j++)
		{
			if (!type)
				cnt += (board[y + i][x + j] != wb[i][j]);

			else
				cnt += (board[y + i][x + j] != bb[i][j]);
		}
	}
	return cnt;
}

int main() 
{
	int n, m, ans, res = INIT;
	cin >> n >> m;
	board.resize(n);

	for (int i = 0; i < n; i++)
		cin >> board[i];

	for (int y = 0; y <= n - MAX_SIZE; y++)
	{
		for (int x = 0; x <= m - MAX_SIZE; x++)
		{
			ans = min(GetCnt(y, x), GetCnt(y, x, 1));
			res = min(res, ans);
		}
	}
	cout << res;
	return 0;
}