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>
#include <string>
#include <queue>
using namespace std;

typedef pair<int, int> P;


int w, h;
int xs, ys, xg, yg, n, c, d, x, y;
int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};

void put_b(int a[][105]) {
  int X, Y;
  if(d == 0) X = 4, Y = 2;
  else X = 2, Y = 4 ;
  for(int i = 0; i < Y; i++)
    for(int j = 0; j < X; j++)
      a[y + i][x + j] = c;
}

bool bfs(int a[][105]) {
  int cs = a[ys][xs];
  if(cs != a[yg][xg]) return false;

  //cout << ys << xs << endl;
  queue<P> que;
  que.push(P(xs, ys));
  while(que.size()) {
    P p = que.front();
    que.pop();
    if(p.first == xg && p.second == yg) return true;
    for(int i = 0; i < 4; i++) {
      int nx = p.first + dx[i], ny = p.second + dy[i];
      if(0 < nx && nx <= w && 0 < ny && ny <= h && a[ny][nx] == cs) {
	que.push(P(nx, ny));
	a[ny][nx] = 0;
      }
    }
  }
  return false;
}
int main() {
  while(cin >> w >> h, w != 0 || h != 0) {
    int a[105][105] = {};
    cin >> xs >> ys;
    cin >> xg >> yg;
    cin >> n;
  
    while(n--) {
      cin >> c >> d >> x >> y;
      put_b(a);
    }
    /*
     for(int i = 0; i < h; i++){
      for(int j = 0; j < w; j++)
      cout << a[i][j];
      cout << endl;
      }
    */
    if(bfs(a) == true) cout << "OK" << endl;
    else cout << "NG" << endl;
  }
  return 0;
}

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

int dx[4] = { 1, 0, -1, 0 };
int dy[4] = { 0, 1, 0, -1 };


class cordinate
{

public:
	int x;
	int y;

};

int main()
{
	while(1)
	{


		int w;
		int h;
		cin >> w >> h; 
		if(w == 0 && h == 0)
		{
			break;
		}
		int xs;
		int ys;
		cin >> xs >> ys;
		int xg;
		int yg;
		cin >> xg >> yg;
		int n;
		cin >> n;

		vector<vector<int >> vobj;

		for(int i = 0; i < h; i++)
		{
			vector<int> lineobj;
			for(int j = 0; j < w; j++)
			{

				lineobj.push_back(0);

			}
			vobj.push_back(lineobj);

		}
		for(int i = 0; i < n; i++)
		{
			int c, d, x, y;
			cin >> c >> d >> x >> y;
			x--;
			y--;

			if(d == 0)
			{
				vobj[x][y] = c;
				vobj[x + 1][y] = c;
				vobj[x + 2][y] = c;
				vobj[x + 3][y] = c;
				vobj[x][y + 1] = c;
				vobj[x + 1][y + 1] = c;
				vobj[x + 2][y + 1] = c;
				vobj[x + 3][y + 1] = c;
			}
			else if(d == 1)
			{
				vobj[x][y] = c;
				vobj[x][y + 1] = c;
				vobj[x][y + 2] = c;
				vobj[x][y + 3] = c;
				vobj[x + 1][y] = c;
				vobj[x + 1][y + 1] = c;
				vobj[x + 1][y + 2] = c;
				vobj[x + 1][y + 3] = c;
			}
		}

		int startColor;
		startColor = vobj[xs - 1][ys - 1];
		queue<cordinate> que;

		cordinate obj;
		obj.x = xs - 1;
		obj.y = ys - 1;
		que.push(obj);
		bool flag = false;
		while(1)
		{
			if(startColor == 0)
			{
				break;
			}
			cordinate buf;
			buf = que.front();
			que.pop();

			int bx;
			int by;
			bx = buf.x;
			by = buf.y;
			if(bx == xg - 1 && by == yg - 1)
			{
				flag = true;
				break;
			}
			for(int i = 0; i < 4; i++)
			{
				if(bx + dx[i] >= 0 && bx + dx[i] <= w - 1)
				{
					if(by + dy[i] >= 0 && by + dy[i] <= h - 1)
					{
						if(vobj[bx + dx[i]][by + dy[i]] == startColor)
						{
							cordinate newObject;
							newObject.x = bx + dx[i];
							newObject.y = by + dy[i];
							que.push(newObject);

						}
					}
				}
			}
			vobj[bx][by] = -1;

			if(que.size() == 0)
			{
				break;
			}
		}


		if(flag == true)
		{
			cout << "OK" << endl;
		}
		else{
			cout << "NG" << endl;
		}
		/*for(int i = 0; i < w - 1; i++)
		{
			for(int j = 0; j < h - 1; j++)
			{
				cout << vobj[i][j] << " ";
			}
			cout << endl;
		}  */

	}



}

C++: #include <stdio.h>

void put(int,int,int,int);
void tansaku(int,int);

const int nashi=-1;
const int tootta=10;

int field[102][102];
int main(int argc,char* argv[]){
	while(1){
		int x_size,y_size;
		int sx,sy;
		int gx,gy;
		int n;
		scanf("%d %d",&x_size,&y_size);
		if(x_size==0)
			return 0;

		scanf("%d %d",&sx,&sy);
		scanf("%d %d",&gx,&gy);
		scanf("%d",&n);

		for(int i=0;i<y_size+2;i++)
			for(int j=0;j<x_size+2;j++)
				field[i][j]=nashi;

		for(int i=0;i<n;i++){
			int c,d,x,y;
			scanf("%d %d %d %d",&c,&d,&x,&y);
			put(c,d,x,y);
		}

		tansaku(sx,sy);
		if(field[gy][gx]==tootta)
			printf("OK\n");
		else
			printf("NG\n");
	}
}

void put(int c,int d,int x,int y){
	const int size[2][2]={{4,2},{2,4}};
	for(int i=0;i<size[d][1];i++){
		for(int j=0;j<size[d][0];j++){
			field[y+i][x+j]=c;
		}
	}
}

void tansaku(int sx,int sy){
	int c=field[sy][sx];
	field[sy][sx]=tootta;
	if(field[sy][sx-1]==c)
		tansaku(sx-1,sy);
	if(field[sy][sx+1]==c)
		tansaku(sx+1,sy);
	if(field[sy-1][sx]==c)
		tansaku(sx,sy-1);
	if(field[sy+1][sx]==c)
		tansaku(sx,sy+1);
}

C++: #include<iostream>
#include<cstdio>
using namespace std;
int w,h,xs,ys,xg,yg,n;
int c,d,x,y,ans=0,f=0;
int map[101][101]={0},v[101][101]={0};
int root(int x,int y,int vmap[][101]){
	int mx[]={0,1,0,-1},fx;
	int my[]={1,0,-1,0},fy;
	if(x==xg&&y==yg){
		f=1;
		return f;
	}
	for(int i=0;i<4;i++){
		fx=x+mx[i];
		fy=y+my[i];
		if(map[fy][fx]==map[xs][ys]&&fy>=0&&fy<h&&fx>=0&&fx<w&&vmap[fy][fx]==0){
			vmap[y][x]=1;
			return root(fx,fy,vmap);
		}
	}
	return f;
}
int main(){
	scanf("%d %d",&w ,&h);
	while(w!=0&&h!=0){
		scanf("%d %d %d %d %d",&xs ,&ys ,&xg ,&yg ,&n);
		for(int i=0;i<n;i++){
			scanf("%d %d %d %d",&c ,&d ,&x ,&y);
			if(d==0){
				for(int i=x;i<x+4;i++){
					for(int e=y;e<y+2;e++){
						map[e][i]=c;
					}
				}
			}
			if(d==1){
				for(int i=x;i<x+2;i++){
					for(int e=y;e<y+4;e++){
						map[e][i]=c;
					}
				}
			}
		}
		/*for(int i=0;i<w;i++){
			for(int i1=0;i1<h;i1++){
				printf("%d ",map[i][i1]);
			}printf("\n");
		}*/
		x=xs;
		y=ys;
		ans=root(x,y,v);
		if(ans==1){
			printf("OK\n");
		}
		else{
			printf("NG\n");
		}
		for(int i=0;i<101;i++){
			for(int i1=0;i1<101;i1++){
				map[i][i1]=0;
				v[i][i1]=0;
			}
		}
		f=0;
		ans=0;
		scanf("%d %d",&w ,&h);
	}
	return 0;
}