Go: package main

import (
	"bufio"
	"os"
	"strings"
	"strconv"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)

var (
	dx = []int{0, -1, 0, 1}
	dy = []int{1, 0, -1, 0}
)

func main() {
	for scanner.Scan() {
		buf := strings.Split(scanner.Text(), " ")
		w, _ := strconv.Atoi(buf[0])
		h, _ := strconv.Atoi(buf[1])
		if w == 0 && h == 0 {
			break
		}
		scanner.Scan()
		buf_ := strings.Split(scanner.Text(), " ")
		xs, _ := strconv.Atoi(buf_[0])
		ys, _ := strconv.Atoi(buf_[1])
		scanner.Scan()
		buf__ := strings.Split(scanner.Text(), " ")
		xg, _ := strconv.Atoi(buf__[0])
		yg, _ := strconv.Atoi(buf__[1])
		xs--
		ys--
		xg--
		yg--
		scanner.Scan()
		n, _ := strconv.Atoi(scanner.Text())
		field := make([][]int, 100)
		for i := range  field {
			field[i] = make([]int, 100)
		}
		visited := make([][]bool, 100)
		for i := range visited {
			visited[i] = make([]bool, 100)
		}
		for i := 0; i < n; i++ {
			scanner.Scan()
			buf___ := strings.Split(scanner.Text(), " ")
			c, _ := strconv.Atoi(buf___[0])
			d, _ := strconv.Atoi(buf___[1])
			x, _ := strconv.Atoi(buf___[2])
			y, _ := strconv.Atoi(buf___[3])
			x--
			y--
			switch d {
			case 0:
				for j := 0; j < 4; j++ {
					for k := 0; k < 2; k++ {
						field[x+j][y+k] = c
					}
				}
			case 1:
				for j := 0; j < 2; j++ {
					for k := 0; k < 4; k++ {
						field[x+j][y+k] = c
					}
				}
			}
		}
		if field[xs][ys] != field[xg][yg] || // スタートとゴールの色が等しくないと"NG"
			field[xs][ys] == 0 { // スタートの色が無職
			fmt.Println("NG")
			continue
		}
		Q := make([]Entry, 0)
		visited[xs][ys] = true
		Q = append(Q, Entry{xs, ys})
		for len(Q) > 0 {
			row := Q[0].x
			col := Q[0].y
			Q = Q[1:]
			for i := 0; i < 4; i++ {
				if 0 <= row+dx[i] && row+dx[i] < w &&
					0 <= col+dy[i] && col+dy[i] < h && // 移動可能な範囲内かどうか
					!visited[row + dx[i]][col + dy[i]] && // 訪問済みか
					field[row+dx[i]][col+dy[i]]==field[row][col] { // 色が同じかどうか
						visited[row+dx[i]][col+dy[i]] = true
						Q = append(Q, Entry{row+dx[i],col+dy[i]})
				}
			}
		}
		if visited[xg][yg] {
			fmt.Println("OK")
		} else {
			fmt.Println("NG")
		}
	}
}

type Entry struct {
	x, y int
}

C++: #include<iostream>
using namespace std;

int Array[200][200];
bool is_goal = false;
#define START 20
#define GOAL 30

void DFS(int h,int w,int c){

  if(!is_goal){

    if(Array[h][w] == GOAL){
      is_goal = true;
      return;
    }

    if(Array[h][w] != c || Array[h][w] == 0){
      return;
    }

    int tmp=Array[h][w];

    Array[h][w] = 0;

    DFS(h-1,w,tmp);
    DFS(h,w+1,tmp);
    DFS(h+1,w,tmp);
    DFS(h,w-1,tmp);
  }

}

int main(){

    while(1){
      int H,W;
      int Start[2],Goal[2];
      int BlockNum;
      int color,dir,xpos,ypos;

      is_goal = false;

      for(int i=0;i<200;i++){
        for(int j=0;j<200;j++){
          Array[i][j] = 0;
        }
      }

      cin >> H >> W;

      if(H == 0 && W == 0){
        break;
      }

      cin >> Start[0] >> Start[1];

      cin >> Goal[0] >> Goal[1];

      cin >> BlockNum;

      for(int i=0;i<BlockNum;i++){
        cin >> color >> dir >> xpos >> ypos;
        for(int i=0;i<4;i++){
          for(int j=0;j<2;j++){
            if(!dir){//?¨?
              Array[xpos+i][ypos+j] = color;
            }
            else{
              Array[xpos+j][ypos+i] = color;
            }
          }
        }
      }
      Array[Goal[0]][Goal[1]] = GOAL;
      /*for(int i=1;i<=H;i++){
        for(int j=1;j<=W;j++){
          cout << Array[i][j];
        }
        cout << endl;
      }*/

      DFS(Start[0],Start[1],Array[Start[0]][Start[1]]);

      if(is_goal){
        cout << "OK" << endl;
      }
      else{
        cout << "NG" << endl;
      }

  }
    return 0;
}

C++: /*****include*****/
#include <iostream>
#include <fstream>
#include <queue>

/*****名前空間*****/
using namespace std;

/*****グローバル変数置き場*****/
/*****その他関数置き場*****/
/*****main関数*****/
int main(){
	/*****変数置き場*****/
	int width;
	int height;
	int pField[101][101];
	int pVisited[101][101];
	int xs,ys;
	int xg,yg;
	int xn,yn;
	int x2,y2;
	int c,d,x,y;
	int n;
	queue<int> Qx;
	queue<int> Qy;
	int cs;
	int dx[] = {0,1,0,-1};
	int dy[] = {-1,0,1,0};
	/*****ファイルオープン*****/	
	/*ofstream fout("output.txt");
	ifstream fin("input.txt");
	if(!fout || !fin){
		cout << "Can't open the file.\n";
		return;
	}*/
	
	/*****処理部*****/
	while(1){
		xn = 0;
		yn = 0;
		for(int i=0;i<101;i++){
			for(int j=0;j<101;j++){
				pVisited[i][j] = 0;
				pField[i][j] = 0;
			}
		}
		cin >> width >> height;
		if(width == 0 && height == 0)	break;
		//int *pField = new int [height][width];
		//int *pVisited = new int [height][width];
		cin >> xs >> ys;
		cin >> xg >> yg;
		cin >> n;
		for(int i=0;i<n;i++){
			cin >> c >> d >> x >> y;
			if(d==0){
				for(int j=0;j<2;j++){
					for(int k=0;k<4;k++){
						pField[j+y][k+x] = c;
					}
				}
			}else{
				for(int j=0;j<4;j++){
					for(int k=0;k<2;k++){
						pField[j+y][k+x] = c;
					}
				}
			}
		}
		/*for(int i=0;i<21;i++){
			for(int j=0;j<21;j++){
				cout << pField[i][j];
			}
			cout << endl;
		}*/
		cs = pField[ys][xs];
		//cout << cs << endl;
		Qx.push(xs);
		Qy.push(ys);
		pVisited[ys][xs] = 1;
		while(!(Qx.empty() && Qy.empty())){
			xn = Qx.front();
			Qx.pop();
			yn = Qy.front();
			Qy.pop();
			//cout << yn << " " << xn << endl;
			/*if(xn == xg && yn == yg){
				break;
			}*/
			for(int i=0;i<4;i++){
				x2 = xn + dx[i];
				y2 = yn + dy[i];
				if(pField[y2][x2]==cs){
					if(!pVisited[y2][x2]){
						Qx.push(x2);
						Qy.push(y2);
						pVisited[y2][x2] = 1;
					}
				}
			}
		}
		/*for(int i=0;i<21;i++){
			for(int j=0;j<21;j++){
				cout << pVisited[i][j];
			}
			cout << endl;
		}*/
		if(pVisited[yg][xg]){
			cout << "OK" << endl;
		}else{
			cout << "NG" << endl;
		}
	}
	/*****処理終了後*****/
	/*fout.close();
	fin.close();*/
	//delete[] pField;
	//delete[] pVisited;
	return 0;
}

C++: #include <iostream>
using namespace std;

int w, h, xs, ys, xg, yg, n, sc;
int map[101][101];
int dx[] = {1, 0, -1, 0},	dy[] = {0, 1, 0, -1};
int hx[] = {0, 1, 2, 3, 0, 1, 2 ,3}, hy[] = {0, 0, 0, 0, 1, 1, 1, 1};
int vx[] = {0, 0, 0, 0, 1, 1, 1, 1}, vy[] = {0, 1, 2, 3, 0, 1, 2, 3};
bool flag = false;

void dfs(int x, int y){
	if(x == xg && y == yg){
		flag = true;
		return;
	}
	map[y][x] = 9;
	for(int i = 0; i < 4; i++){
		int nx = x + dx[i], ny = y + dy[i];
		if(1 <= nx && nx <= w && 1 <= ny && ny <= h && map[ny][nx] == sc)	dfs(nx, ny);
	}
	return;
}

int main(void){
	while(true){
		int c, d, x, y;
		flag = false;
		cin >> w >> h;
		if(w == 0 && h == 0)	break;
		cin >> xs >> ys >> xg >> yg >> n;
		for(int i = 0; i < n; i++){
			cin >> c >> d >> x >> y;
			if(d == 0){
				for(int j = 0; j < 8; j++)	map[y+hy[j]][x+hx[j]] = c;
			}else{
				for(int j = 0; j < 8; j++)	map[y+vy[j]][x+vx[j]] = c;
			}
		}
		sc = map[ys][xs];
		dfs(xs, ys);
		if(flag)	cout << "OK" << endl;
		else cout << "NG" << endl;
	}
  return 0;
}