#1#6 80分记忆化搜索求调!

#include<bits/stdc++.h>
using namespace std;
const int N = 110;
int mem[N][N];
int arr[N][N];
int n, m;
int dfs(int i, int j)
{
	if (mem[i][j])return mem[i][j];
	int sum = 0;
	if (i-1>0&&arr[i][j] > arr[i - 1][j])sum =max(sum, dfs(i - 1, j));
	if (i+1<=m &&arr[i][j] > arr[i+1][j])sum = max(sum,dfs(i+1, j));
	if (j-1>0&&arr[i][j] > arr[i][j-1])sum = max(sum,dfs(i, j-1));
	if (j+1<=n &&arr[i][j] > arr[i][j+1])sum = max(sum,dfs(i ,j+1));
	mem[i][j] = sum+1;
	return mem[i][j];
}
signed main()
{
	int ans = 1;
	
	cin >> n >> m;
	for (int i = 1; i <= n; i++)
		for (int j = 1; j <= m; j++)
			cin >> arr[i][j];

	for (int i = 1; i <= n; i++)
		for (int j = 1; j <= m; j++)
		{
			if (!mem[i][j]) dfs(i, j);

			ans = max(ans, mem[i][j]);
		}
	cout << ans;
	return 0;
}