14500.py

import sys
input=lambda:sys.stdin.readline().rstrip()
N,M=map(int,input().split())
graph=[list(map(int,input().split())) for _ in range(N)]
m=0
t=[[(0,0),(0,1),(0,2),(0,3)],[(0,0),(1,0),(2,0),(3,0)] # ㅡㅣ
   ,[(0,0),(0,1),(1,0),(1,1)] # ㅁ
   ,[(0,0),(0,1),(0,2),(1,0)],[(0,0),(0,1),(0,2),(-1,0)],[(0,0),(1,0),(2,0),(0,1)],[(0,0),(1,0),(2,0),(0,-1)]
   ,[(0,0),(0,1),(0,2),(1,2)],[(0,0),(0,1),(0,2),(-1,2)],[(0,0),(1,0),(2,0),(2,1)],[(0,0),(1,0),(2,0),(2,-1)]
   ,[(0,0),(0,1),(0,2),(1,1)],[(0,0),(0,1),(0,2),(-1,1)],[(0,0),(1,0),(2,0),(1,1)],[(0,0),(1,0),(2,0),(1,-1)]#ㅗ
   ,[(0,0),(0,1),(-1,1),(1,0)],[(0,0),(0,1),(1,1),(-1,0)],[(0,0),(1,0),(1,1),(0,-1)],[(0,0),(1,0),(1,-1),(0,1)]]
for j in range(N):
    for i in range(M):
        for k in t:
            s=0
            for x,y in k:
                    if 0<=i+x<M and 0<=j+y<N:
                        s+=graph[j+y][i+x]
                    else:
                        s=0
                        break
            m=max(m,s)
print(m)