h,w,sy,sx=map(int,input().split())
a=[]
for _ in range(h):
  a.append(list(map(int,input().split())))

import heapq
class HQ:
  def __init__(self,a):
    self.hq=a.copy()
    heapq.heapify(self.hq)
  
  def get(self):
    if self.hq:
      return self.hq[0]
    else:
      return False
  
  def len(self):
    return len(self.hq)

  def pop(self):
    if self.hq:
      return heapq.heappop(self.hq)
    else:
      return False
  
  def append(self,i):
    heapq.heappush(self.hq,i)

dxdy=[(0,1),(1,0),(0,-1),(-1,0)]
seen=[[False]*w for i in range(h)]

now=0
hq=HQ([(a[sy-1][sx-1],sy-1,sx-1)])
added=[[False]*w for i in range(h)]

while hq.len()>0:
  c,x,y=hq.pop()
  #print(c,x,y,now)
  if seen[x][y]:continue
  seen[x][y]=True
  if x==sy-1 and y==sx-1:
    now+=c
  else:
    if now>c:
      now+=c
    else:
      print('No')
      exit()
  for dx,dy in dxdy:
    nx,ny=x+dx,y+dy
    if 0<=nx<h and 0<=ny<w and not added[nx][ny]:
      hq.append((a[nx][ny],nx,ny))
      added[nx][ny]=True

print('Yes')