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<string>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<complex>
#include<cmath>
#include<algorithm>
#include<map>
#include<vector>
#include<sstream>
#include<iostream>
#include<queue>
using namespace std;
const int dx[] = {1,0,-1,0},dy[] = {0,1,0,-1};
struct point{
    int x,y;
    point(){}
    point(int a, int b){x = a;y = b;}
};
int main(void){

    int w,h;
    while(cin>>w>>h,w){
        int xs,ys,xg,yg,n;
        cin>>xs>>ys>>xg>>yg>>n;
        int field[120][120] = {{0}};
        for(int i = 0;i < n;i++){
            int c,d,x,y;
            int dw = 4,dh = 2;
            cin>>c>>d>>x>>y;
            if(d)swap(dw,dh);
            for(int di = y;di < dh + y; di++){
                for(int dj = x;dj < dw + x;dj++){
                    field[di][dj] = c;
                }
            }
        }
        int C = field[xs][ys];
        bool vis[120][120] = {{false}};
        queue<point> Q;
        Q.push(point(xs,ys));
        if(field[xg][yg] != C || C == 0)cout<<"NG"<<endl;
        else {
            while(!Q.empty()){
                point P = Q.front();
                Q.pop();
                for(int i = 0;i < 4;i++){
                    point p = point(P.x + dx[i],P.y + dy[i]);
                    if(1 <= p.x && p.x <= w && 1 <= p.y && p.y <= h){
                        if(!vis[p.x][p.y]&&field[p.x][p.y] == C){

                            vis[p.x][p.y] = true;
                            Q.push(p);
                        }
                    }
                }
            }

        if(vis[xg][yg])cout<<"OK"<<endl;
        else cout<<"NG"<<endl;
        }
/*
        for(int i = 0;i < h;i++){
            for(int j = 0;j < w;j++){
                cout<<field[i][j]<<" ";
            }
            cout<<endl;
        }
        cout<<endl<<endl;
        for(int i = 0;i < h;i++){
            for(int j = 0;j < w;j++){
                cout<<vis[i][j]<<" ";
            }
            cout<<endl;
        }*/
        //cout<<C<<"---"<<field[xg][yg]<<endl;
    }


    return 0;
}

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


int F[1000][1000];

//?????????????????????
void r(int yy,int xx,int z){
 if(F[yy][xx]!=z){
	return ;
 }

F[yy][xx]=10;

r(yy-1,xx,z);
r(yy,xx+1,z);
r(yy+1,xx,z);
r(yy,xx-1,z);

}




int main(){
 int w,h,xs,ys,xg,yg,n;
 int c,d,x,y;

while(1){
 cin>>w>>h;

//?????????????????????0???????????????
 if(w==0&&h==0)break;
//???????????????????????????????????\?????°????±??????£???????????????
 cin>>xs>>ys>>xg>>yg>>n;

//n?????°???????????????????????????
for(int i=0;i<n;i++){
	cin>>c>>d>>x>>y;//?????????????????¨????????±????????????
	if(d==0){
		F[x  ][y]=c;
		F[x+1][y]=c;
 		F[x+2][y]=c;
 		F[x+3][y]=c;
 		F[x  ][y+1]=c;
 		F[x+1][y+1]=c;
 		F[x+2][y+1]=c;
 		F[x+3][y+1]=c;
	}
	if(d==1){
		F[x][y  ]=c;
 		F[x][y+1]=c;
		F[x][y+2]=c;
		F[x][y+3]=c;
 		F[x+1][y  ]=c;
		F[x+1][y+1]=c;
		F[x+1][y+2]=c;
 		F[x+1][y+3]=c;
	}
}

//??\????????????????????????


//??????????????????
r(xs,ys,F[xs][ys]);
//??´???????????????
if(F[xg][yg]==10){
	cout<<"OK"<<endl;
}else{
	cout<<"NG"<<endl;
}
//???????????????????????????
for(int i=1;i<=w;i++){
	for(int g=1;g<=w;g++){
		F[i][g]=6;
	}
}
//?????????????????????
}
return 0;
}

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;
}
+-