#include<bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define pb push_back
#define epb emplace_back
#define inf 1e9+1
#define linf 1e18+1
#define f first
#define s second
#define pii pair<int,int>
#define pll pair<ll,ll>
using namespace std;
int main(){
int n;cin>>n;
int m;cin>>m;
int ans=-inf;
int a[n+1][m+1];
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
cin>>a[i][j];
}
}
int mx1[n+2][m+2],mx2[n+2][m+2],mx3[n+2][m+2],mx4[n+2][m+2];
for(int i=0;i<=n+1;i++){
for(int j=0;j<=m+1;j++){
mx1[i][j]=mx2[i][j]=mx3[i][j]=mx4[i][j]=-inf;
}
}
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
mx1[i][j]=max({mx1[i-1][j],mx1[i][j-1],a[i][j]+i+j});
}
}
for(int i=n;i>=1;i--){
for(int j=1;j<=m;j++){
mx2[i][j]=max({mx2[i+1][j],mx2[i][j-1],a[i][j]+j-i});
}
}
for(int i=1;i<=n;i++){
for(int j=m;j>=1;j--){
mx3[i][j]=max({mx3[i-1][j],mx3[i][j+1],a[i][j]-j+i});
}
}
for(int i=n;i>=1;i--){
for(int j=m;j>=1;j--){
mx4[i][j]=max({mx4[i+1][j],mx4[i][j+1],a[i][j]-i-j});
}
}
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
ans=max(ans,mx1[i][j]-a[i][j]-i-j);
ans=max(ans,mx2[i][j]-a[i][j]-j+i);
ans=max(ans,mx3[i][j]-a[i][j]-i+j);
ans=max(ans,mx4[i][j]-a[i][j]+i+j);
}
}
cout<<ans-1;
return 0;
}
