#include <bits/stdc++.h> using namespace std; const int N = 1e3 + 10; int n, m, a[N][N], val[2][N][N], b[N][N]; int get(){ for (int i = 0; i < N; i ++) for (int j = 0; j < N; j ++) val[0][i][j] = val[1][i][j] = -2e9; for (int i = 1; i <= n; i ++) for (int j = m; j > 0; j --) val[0][i][j] = max(val[0][i][j + 1], -a[i][j] -j); for (int i = n; i > 0; i --) for (int j = 1; j <= m; j ++) val[1][i][j] = max(val[1][i + 1][j], a[i][j] -i); int ans = -1e9; for (int i = 1; i <= n; i ++) for (int j = 1; j <= m; j ++) ans = max(ans, val[0][i][j] + j + val[1][i][j] + i - 1); return ans; } void rotate(){ for (int i = 1; i <= n; i ++) for (int j = 1; j <= m; j ++) b[j][n - i + 1] = a[i][j]; swap(n, m); for (int i = 1; i <= n; i ++) for (int j = 1; j <= m; j ++) a[i][j] = b[i][j]; } int main(){ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> m; for (int i = 1; i <= n; i ++) for (int j = 1; j <= m; j ++) cin >> a[i][j]; int overall = -2e9; for (int i = 0; i < 4; i ++){ overall = max(overall, get()); rotate(); } cout << overall << endl; }