"""

"""

import sys
from sys import stdin
from collections import deque

H,W = map(int,stdin.readline().split())

A = [ list(map(int,stdin.readline().split())) for i in range(H) ]

dp = [[[float("-inf"),float("-inf")] for j in range(W)] for i in range(H)]

dp[0][0][0] = A[0][0]

for i in range(H):

    for j in range(W):

        for k in range(2):

            now = dp[i][j][k]
            if i != H-1:

                if A[i+1][j] < now:
                    dp[i+1][j][k] = max(dp[i+1][j][k] , now+A[i+1][j])
                if k == 0 and (i+1,j) != (H-1,W-1):
                    dp[i+1][j][1] = max(dp[i+1][j][1] , now)

            if j != W-1:

                if A[i][j+1] < now:
                    dp[i][j+1][k] = max(dp[i][j+1][k] , now+A[i][j+1])
                if k == 0 and (i,j+1) != (H-1,W-1):
                    dp[i][j+1][1] = max(dp[i][j+1][1] , now)

#print (dp)

if dp[-1][-1][0] != float("-inf") or dp[-1][-1][1] != float("-inf"):
    print ("Yes")
else:
    print ("No")