m,n=input().split() m,n=int(m),int(n) x=0 ; y=0 a=[] for i in range(m+1): t=input().split() a.append(t) for i in range(m+1): for i in range(n+1): if i == 0 or i == m - 1 or j == 0 or j == n - 1: s = s + int(a[i][j]) print(s)