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 <bits/stdc++.h>
using namespace std;

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

void dfs(int y, int x, vector<vector<int>>& v) {
    int c = v[y][x];
    v[y][x] = -1;
    for(int i=0; i<4; ++i) {
        int ny = y + dy[i], nx = x + dx[i];
        if(ny < 0 || v.size() <= ny || nx < 0 || v[0].size() <= nx || v[ny][nx] != c) {
            continue;
        }
        dfs(ny, nx, v);
    }
}

int main() {
    int w, h;
    while(cin >> w >> h, w) {
        int xs, ys, xg, yg;
        cin >> xs >> ys >> xg >> yg;
        xs--; ys--; xg--; yg--;

        vector<vector<int>> v(h, vector<int>(w));
        int n;
        cin >> n;
        for(int i=0; i<n; ++i) {
            int c, d, x, y;
            cin >> c >> d >> x >> y;
            x--; y--;
            int size[2] = {2, 4};
            for(int j=y; j<y+size[d]; ++j) {
                for(int k=x; k<x+size[(d+1)%2]; ++k) {
                    v[j][k] = c;
                }
            }
        }
        dfs(ys, xs, v);
        if(v[yg][xg] == -1) {
            cout << "OK" << endl;
        } else {
            cout << "NG" << endl;
        }
    }
}

C++: #include<iostream>
#include<queue>
#include<vector>
#include<list>

typedef struct block
{
	int x;
	int y;
	int h;
	int w;
	int color;
}block;

block blocks[1280];

std::queue<int> que;
std::list<int> adjacive[1280];

void makelist(int n);
bool BFS(int start,int goal);

int main()
{
	int n,w,h,xs,ys,xg,yg,start,goal;
	while(1)
	{
		while(!que.empty()){que.pop();}
		start=-1;
		goal=-1;
		std::cin>>w>>h;
		if(w==0&&h==0)break;
		std::cin>>xs>>ys>>xg>>yg>>n;
		for(int i=0;i<n;i++)
		{
			int c,d,x,y;
			std::cin>>c>>d>>x>>y;
			blocks[i].color=c;
			blocks[i].x=x;
			blocks[i].y=y;
			if(d==0)
			{
				blocks[i].h=2;
				blocks[i].w=4;
			}
			else
			{
				blocks[i].h=4;
				blocks[i].w=2;
			}
			if(blocks[i].x<=xs&&blocks[i].x+blocks[i].w>=xs&&blocks[i].y<=ys&&blocks[i].y+blocks[i].h>=ys)
			{
				start=i;
			}
			else if(blocks[i].x<=xg&&blocks[i].x+blocks[i].w>=xg&&blocks[i].y<=yg&&blocks[i].y+blocks[i].h>=yg)
			{
				goal=i;
			}
		}
		makelist(n);
		if(BFS(start,goal))
		{
			std::cout<<"OK"<<std::endl;
		}
		else
		{
			std::cout<<"NG"<<std::endl;
		}
	}
	return 0;
}

void makelist(int n)
{
#define x1 blocks[i].x
#define y1 blocks[i].y
#define h1 blocks[i].h
#define w1 blocks[i].w
#define x2 blocks[j].x
#define y2 blocks[j].y
#define h2 blocks[j].h
#define w2 blocks[j].w

	for(int i=0;i<n;i++)
	{
		adjacive[i].clear();
		for(int j=0;j<n;j++)
		{
			if(blocks[i].color==blocks[j].color)
			{
				if((x1==x2+w2&&y1<=y2+h2-1&&y1+h1-1>=y2)||(x2==x1+w1&&y1<=y2+h2-1&&y1+h1-1>=y2)||(y1==y2+h2&&x1<=x2+w2-1&&x1+w1-1>=x2)||(y2==y1+h1&&x1<=x2+w2-1&&x1+w1-1>=x2))
				{
					adjacive[i].push_back(j);
				}
			}
		}
	}
}

bool BFS(int start,int goal)
{
	int survey;
	que.push(start);
	
	while(!que.empty())
	{
		survey=que.front();
		que.pop();
		for(std::list<int>::iterator it=adjacive[survey].begin();it!=adjacive[survey].end();it++)
		{
				que.push(*it);
		}
		adjacive[survey].clear();
		if(survey==goal)
		{
			return true;
		}
	}
	return false;
}

C++: #include<iostream>
using namespace std;
int a[200][200]={},sx,sy,gx,gy;
int f(int i,int j){
	if(i==gy && j==gx)
		return 1;
	if(a[i+1][j]==a[sy][sx])
		if(f(i+1,j)==1)
			return 1;
	if(a[i][j+1]==a[sy][sx])
		if(f(i,j+1)==1)
			return 1;
	if(a[i-1][j]==a[sx][sy])
		if(f(i-1,j)==1)
			return 1;
	if(a[i][j-1]==a[sx][sy])
		if(f(i,j-1)==1)
			return 1;
	return 0;
}
int main(){
	while(1){
		int w,h,n,c,d,x,y;
		cin>>w>>h;
		if(w==0 && h==0)
		break;
		for(int i=0;i<h;i++)
		for(int j=0;j<w;j++)
			a[i][j]=0;
		cin>>sx>>sy;
		cin>>gx>>gy;
		cin>>n;
		for(int i=0;i<n;i++){
			cin>>c>>d>>x>>y;
			if(d==0){
				for(int i=0;i<2;i++)
				for(int j=0;j<4;j++)
					a[y+i][x+j]=c;
			}
			if(d==1){
				for(int i=0;i<4;i++)
				for(int j=0;j<2;j++)
					a[y+i][x+j]=c;
			}
		}
		if(a[sx][sy]!=a[gx][gy])
		cout<<"NG"<<endl;
		else if(f(sy,sx)==0)
		cout<<"NG"<<endl;
		else if(f(sx,sy)==1)
		cout<<"OK"<<endl;
	}
	return 0;
}

C++: #include<iostream>
#include<queue>

using namespace std ;

int map[ 100 ][ 100 ] ;
int w ,h ;
int gx ,gy ;
int way ;

struct ST
{
	int x ;
	int y ;
} ;

ST s ;

void ans()
{
	queue< ST > que ;
	int mx[ 4 ] = { 1 ,0 ,0 ,-1 } ;
	int my[ 4 ] = { 0 ,1 ,-1 ,0 } ;
	bool came[ 100 ][ 100 ] = { false } ;
	que.push( s ) ;
	came[ s.y ][ s.x ] = true ;
	while( ! que.empty() )
	{
		s = que.front() ;
		if( s.x == gx && s.y == gy )
		{
			cout << "OK" << endl ;
			return ;
		}
		que.pop() ;
		for( int i = 0 ; i < 4 ; i++ )
		{
			s.x += mx[ i ] ;
			s.y += my[ i ] ;
			if( came[ s.y ][ s.x ] == false && map[ s.y ][ s.x ] == way )
			{
				came[ s.y ][ s.x ] = true ;
				que.push( s ) ;
				s.x -= mx[ i ] ;
				s.y -= my[ i ] ;
			}
		}
	}
	cout << "NG" << endl ;
}


int main()
{
	while( cin >> w >> h ,h )
	{
		int n ;
		int color ,muki ,x ,y ;
		cin >> s.x >> s.y ;
		cin >> gx >> gy ;
		cin >> n ;
		while( n )
		{
			n-- ;
			cin >> color >> muki >> x >> y ;
			x-- ;
			y-- ;
			if( muki )
			{
				for( int i = 0 ; i < 4 ; i++ )
				{
					for( int j = 0 ; j < 2 ; j++ )
					{
						map[ y + i ][ x + j ] = color ;
					}
				}
			}
			else
			{
				for( int i = 0 ; i < 2 ; i++ )
				{
					for( int j = 0 ; j < 4 ; j++ )
					{
						map[ y + i ][ x + j ] = color ;
					}
				}
			}
		}
		gx-- ;
		s.x-- ;
		gy-- ;
		s.y-- ;
		way = map[ s.y ][ s.x ] ;
		if( map[ gy ][ gx ] == way )
		{
			ans() ;
		}
		else
		{
			cout << "NA" << endl ;
		}
	}
	return 0 ;
}