#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using mint = atcoder::modint1000000007;

int main(){
	int h,w;
	cin>>h>>w;
	vector<vector<ll>> a(h,vector<ll>(w));
	rep(i,h) rep(j,w) cin>>a.at(i).at(j);
	vector<int> dx={-1,-1,0,1,1,1};
	vector<int> dy={0,1,1,1,0,-1};
	auto isok=[&](int x,int y){
		return 0<=x&&x<h&&0<=y&&y<w;
	};
	auto select=[&](int x,int y,int i,vector<vector<ll>> &b){
		ll res=0;
		while(isok(x,y)){
			res+=b.at(x).at(y);
			x+=dx.at(i);
			y+=dy.at(i);
		}
		return res;
	};
	auto del=[&](int x,int y,int i){
		auto ca=a;
		while(isok(x,y)){
			ca.at(x).at(y)=0;
			x+=dx.at(i);
			y+=dy.at(i);
		}
		return ca;
	};
	ll tmp=0;
	vector<tuple<int,int,int>> xyi;
	rep(ch1,h+w-1){
		int x1=0,y1=0;
		if(ch1>=h) y1=ch1-h+1;
		else x1=ch1;
		rep(i1,6){
			ll tp=select(x1,y1,i1,a);
			if(tmp<tp){
				tmp=tp;
				xyi={{x1,y1,i1}};
			}else if(tmp==tp){
				xyi.push_back({x1,y1,i1});
			}
		}
	}
	ll ans=0;
	for(auto[x1,y1,i1]:xyi){
		auto ca=del(x1,y1,i1);
		rep(ch1,h+w-1){
			int x=0,y=0;
			if(ch1>=h) y=ch1-h+1;
			else x=ch1;
			rep(i,6){
				ans=max(ans,select(x,y,i,ca));
			}
		}
	}
	cout<<ans+tmp<<endl;
}