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
}

Python: # -*- coding: utf-8 -*-
"""
http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=0207

"""
import sys
from sys import stdin
from collections import deque
input = stdin.readline


def solve(w, h, xs, ys, xg, yg, blocks):
    # ????????????????????±????????°???????????????l
    field = [[0] * (w+1) for _ in range(h+1)]
    for c, d, x, y in blocks:
        field[y][x] = c
        field[y][x+1] = c
        field[y+1][x] = c
        field[y+1][x+1] = c

        if d == 0:              #  ?¨????
            field[y][x+2] = c
            field[y][x+3] = c
            field[y+1][x+2] = c
            field[y+1][x+3] = c
        else:                   #  ??????
            field[y+2][x] = c
            field[y+3][x] = c
            field[y+2][x+1] = c
            field[y+3][x+1] = c

    # ????????????????§????????????´????????§?¨??????????
    dy = [-1, 1, 0, 0]
    dx = [0, 0, -1, 1]

    d = [[-1] * (w+1) for _ in range(h+1)] #  ?????¢?´¢?????°??¨???????????¨??????-1???
    Q = deque()
    Q.append((xs, ys))
    d[ys][xs] = 0
    color = field[ys][xs]       #  ?????????????????¨?????§?????????????????????????????°?????¨???????????????

    while Q:
        xc, yc = Q.popleft()        #  ?????¨??°?????§?¨?
        if xc == xg and yc == yg:
            return 'OK'
        for i in range(len(dx)):
            xn = xc + dx[i]
            yn = yc + dy[i]
            #  ?§????????????§???????????? ?????? ??¢?????¢?´¢?????§???????????°??????????????§?????¢?´¢????¶???????
            if 0 < xn <= w and 0 < yn <= h and d[yn][xn] == -1 and field[yn][xn] == color:
                Q.append((xn, yn))
                d[yn][xn] = d[yc][xc] + 1
    return 'NG'


def main(args):
    while True:
        w, h = map(int, input().split())
        if w == 0 and h == 0:
            break
        xs, ys = map(int, input().split())
        xg, yg = map(int, input().split())
        n = int(input())
        blocks = [list(map(int, input().split())) for _ in range(n)]

        result = solve(w, h, xs, ys, xg, yg, blocks)
        print(result)


if __name__ == '__main__':
    main(sys.argv[1:])

Python: from sys import stdin
readline = stdin.readline


from collections import namedtuple
Point = namedtuple('Point', ['x', 'y'])
Block = namedtuple('Block', ['color', 'direction', 'x', 'y'])


def occupation_point(block):
    x, y = block.x, block.y
    d = [(0, 0), (1, 0), (0, 1), (1, 1)]
    for dx, dy in d:
        yield x + dx, y + dy
    if block.direction:
        y += 2
    else:
        x += 2
    for dx, dy in d:
        yield x + dx, y + dy

def paintout(board, start, value):
    color = board[start.y][start.x]
    if color == 0:
        return
    que =[(start.x, start.y)]
    print('cv',color, value)
    while que:
        x,y = que.pop()
        if board[y][x] == color:
            board[y][x] = value
            que.extend([(x + dx, y + dy) for dx, dy in [(-1, 0), (0, -1), (1, 0), (0, 1)]])


def is_reachable(size, start, goal, blocks):
    board = [[0] * (size.x + 2) for _ in range(size.y + 2)]
    for bi in blocks:
        for x, y in occupation_point(bi):
            board[y][x] = bi.color
    paintout(board, start, -1)
    for bi in board:
        print(bi)
    return board[goal.y][goal.x] == -1


while True:
    size = Point(*map(int, readline().split()))
    if size.x == 0:
        break
    start = Point(*map(int, readline().split()))
    goal = Point(*map(int, readline().split()))
    blocks = []
    for _ in range(int(readline())):
        blocks.append(Block(*map(int, readline().split())))
    print('OK' if is_reachable(size, start, goal, blocks) else 'NG')

Python: def block(board, y, x, direction, color):
    # ???
    if direction == 0:
        for i in range(2):
            for j in range(4):
                board[x + i][y + j] = color
    # ??±
    elif direction == 1:
        for i in range(2):
            for j in range(4):
                board[x + j][y + i] = color


def print_board(board):
    for i in range(len(board)):
        print(board[i])


def go_maze(board, s_x, s_y, g_x, g_y):
    place = board[s_x][s_y]
    if place == 0:
        return 'NG'
    x, y = s_x, s_y
    stack = []

    while True:
        # print(x, y)
        board[x][y] = place + 1
        if x + 1 < len(board) and board[x + 1][y] == place:
            x += 1
            stack.append((x, y))
        elif y + 1 < len(board[x]) and board[x][y + 1] == place:
            y += 1
            stack.append((x, y))
        elif x - 1 > 0 and board[x - 1][y] == place:
            x -= 1
            stack.append((x, y))
        elif y - 1 > 0 and board[x][y - 1] == place:
            y -= 1
            stack.append((x, y))
        else:
            if len(stack) == 0 and board[x + 1][y] != place and board[x][y + 1] != place and board[x - 1][y] != place and board[x][y - 1] != place:
                return 'NG'
            (x, y) = stack.pop()

        if x == g_x and y == g_y:
            return 'OK'


def main():
    while True:
        w, h = map(int, input().split())
        if w == 0 and h == 0:
            break

        board = [[0 for _ in range(w)] for _ in range(h)]
        s_x, s_y = map(int, input().split())
        g_x, g_y = map(int, input().split())
        for _ in range(int(input())):
            color, direction, x, y = map(int, input().split())
            block(board, x, y, direction, color)

        # print_board(board)
        print(go_maze(board, s_y, s_x, g_y, g_x))


if __name__ == '__main__':
    main()