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 a=0;
int F[102][102];
void DFS(int Xs,int Ys,int c,int Xg,int Yg){
  if(F[Xs][Ys]!=c){
    return;
  }else if(Xs==Xg&&Ys==Yg){
    a=1;
    return;
  }
 F[Xs][Ys]=0;
 DFS(Xs-1,Ys,c,Xg,Yg);
 DFS(Xs,Ys-1,c,Xg,Yg);
 DFS(Xs+1,Ys,c,Xg,Yg);
 DFS(Xs,Ys+1,c,Xg,Yg);
}

int main(){
  while(1){
   int w,h,xs,ys,xg,yg,n,C;
   cin>>w>>h;
   if(w==0&&h==0){
     break;
   }
   cin>>xs>>ys>>xg>>yg>>n;
   int c[n],d[n],x[n],y[n];
   for(int i=0;i<n;i++){
     cin>>c[i]>>d[i]>>x[i]>>y[i];
     if(xs==x[i]&&ys==y[i]){
       C=c[i];
     }
      for(int j=0;j<4;j++){
        for(int k=0;k<2;k++){
          if(d[i]==0){
           F[x[i+j]][y[i+k]]=c[i];
         }else{
           F[x[i+k]][y[i+j]]=c[i];
         }
       }
     }
    }
    DFS(xs,ys,C,xg,yg);
    if(a==1){
      cout<<"OK"<<endl;
    }else{
      cout<<"NG"<<endl;
    }
  }
}

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[100][100]={0},v[100][100]={0};
int root(int x,int y,int vmap[][100]){
	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[fy][fx]=1;
			return root(fx,fy,vmap);
		}
	}
	return 0;
}
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 w=x;w<x+4;w++){
					for(int h=y;h<y+2;h++){
						map[h][w]=c;
					}
				}
			}
			if(d==1){
				for(int w=x;w<x+2;w++){
					for(int h=y;h<y+4;h++){
						map[h][w]=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<100;i++){
			for(int i1=0;i1<100;i1++){
				map[i][i1]=0;
				v[i][i1]=0;
			}
		}
		f=0;
		ans=0;
		scanf("%d %d",&w ,&h);
	}
	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 ;
}