#include<bits/stdc++.h>
#define ll long long
using namespace std;
 
ll f[2005][2005], a[2005];
 
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    ll n, m, maxn = 0, x=0;
    cin >> m >> n;
    for(int p=1;p<=m;p++){
		for (int i = 1; i <= n; i++) cin >> a[i];
		for (int i = 1; i <= n; i++)
			for (int len = n - i + 1 ; len >= 0; len--)
			{
				int j = i + len - 1;
				f[i][j] = max(f[i - 1][j] + a[i - 1] * pow(2,n - len), f[i][j + 1] + a[j + 1] * pow(2,n - len));
			}
		for (int i = 1; i <= n; i++){
			maxn = max(f[i][i - 1], maxn);
		}
		x=x+maxn;
	}
    cout << x << endl;
    return 0;
}