import std.conv, std.functional, std.range, std.stdio, std.string; import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons; import core.bitop; class EOFException : Throwable { this() { super("EOF"); } } string[] tokens; string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; } int readInt() { return readToken.to!int; } long readLong() { return readToken.to!long; } string COLOR(string s = "") { return "\x1b[" ~ s ~ "m"; } bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } } bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } } int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; } int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); } int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); } void main() { try { for (; ; ) { const M = readInt; const N = readInt; auto A = new int[][](M + 2, N + 2); foreach (x; 1 .. M + 1) foreach (y; 1 .. N + 1) { A[x][y] = readInt; } int[] xs, ys; foreach (x; 0 .. M + 2) foreach (y; 0 .. N + 2) { if (x == 0 || x == M + 1 || y == 0 || y == N + 1) { xs ~= x; ys ~= y; } } const len = cast(int)(xs.length); int ans; auto vis = new bool[][](M + 2, N + 2); void go(int s, int dx, int dy) { for (int x = xs[s], y = ys[s]; ; ) { const xx = x + dx; const yy = y + dy; if (!(1 <= xx && xx <= M && 1 <= yy && yy <= N)) { break; } x = xx; y = yy; vis[x][y] = true; } } foreach (s0; 0 .. len) foreach (dx0; -1 .. +1 + 1) foreach (dy0; -1 .. +1 + 1) if (dx0 || dy0) foreach (s1; 0 .. len) foreach (dx1; -1 .. +1 + 1) foreach (dy1; -1 .. +1 + 1) if (dx1 || dy1) { if ([s0, dx0, dy0] > [s1, dx1, dy1]) continue; foreach (x; 0 .. M + 2) vis[x][] = false; go(s0, dx0, dy0); go(s1, dx1, dy1); int score; foreach (x; 1 .. M + 1) foreach (y; 1 .. N + 1) if (vis[x][y]) { score += A[x][y]; } // if([xs[s0],ys[s0],dx0,dy0,xs[s1],ys[s1],dx1,dy1]==[0,2,1,0,0,3,1,0])writeln(vis," ",score); chmax(ans, score); } writeln(ans); } } catch (EOFException e) { } }