import sys
from collections import deque
sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


H,W = MI()
sx,sy,gx,gy = MI()
B = [[0]*(W+1)]+[[0]+LI2() for _ in range(H)]

flag = [[0]*(W+1) for _ in range(H+1)]
flag[sx][sy] = 1
deq = deque([(sx,sy)])
while deq:
    x,y = deq.pop()
    if 1 <= x-1 <= H and flag[x-1][y] == 0 and abs(B[x-1][y]-B[x][y]) <= 1:
        flag[x-1][y] = 1
        deq.appendleft((x-1,y))
    if 1 <= x+1 <= H and flag[x+1][y] == 0 and abs(B[x+1][y]-B[x][y]) <= 1:
        flag[x+1][y] = 1
        deq.appendleft((x+1,y))
    if 1 <= y-1 <= W and flag[x][y-1] == 0 and abs(B[x][y-1]-B[x][y]) <= 1:
        flag[x][y-1] = 1
        deq.appendleft((x,y-1))
    if 1 <= y+1 <= W and flag[x][y+1] == 0 and abs(B[x][y+1]-B[x][y]) <= 1:
        flag[x][y+1] = 1
        deq.appendleft((x,y+1))
    if 1 <= x-2 <= H and flag[x-2][y] == 0 and B[x-2][y] == B[x][y] and B[x-1][y] < B[x][y]:
        flag[x-2][y] = 1
        deq.appendleft((x-2,y))
    if 1 <= x+2 <= H and flag[x+2][y] == 0 and B[x+2][y] == B[x][y] and B[x+1][y] < B[x][y]:
        flag[x+2][y] = 1
        deq.appendleft((x+2,y))
    if 1 <= y-2 <= W and flag[x][y-2] == 0 and B[x][y-2] == B[x][y] and B[x][y-1] < B[x][y]:
        flag[x][y-2] = 1
        deq.appendleft((x,y-2))
    if 1 <= y+2 <= W and flag[x][y+2] == 0 and B[x][y+2] == B[x][y] and B[x][y+1] < B[x][y]:
        flag[x][y+2] = 1
        deq.appendleft((x,y+2))

if flag[gx][gy]:
    print('YES')
else:
    print('NO')