#include <iostream>
#include <algorithm>

using namespace std;

int r;//行
int c;//列
int a[1000][100];//输入矩阵
int result[1000][1000];//输出矩阵

//递归思想：分别求出上下左右方向的最大长度
int maxLength(int  i, int j)
{
	int left = j - 1;
	int right = j + 1;
	int high = i - 1;
	int low = i + 1;

	int left_value;
	int right_value;
	int high_value;
	int low_value;

	//左侧最大长度
	if (left >= 0 && a[i][left] < a[i][j])
		left_value = maxLength(i, left) + 1;
	else
		left_value = 0;

	//右侧最大长度
	if (right <= c - 1 && a[i][right] < a[i][j])
		right_value = maxLength(i, right) + 1;
	else
		right_value = 0;

	//上侧最大长度
	if (high >= 0 && a[high][j] < a[i][j])
		high_value = maxLength(high, j) + 1;
	else
		high_value = 0;

	//下侧最大长度
	if (low <= r - 1 && a[low][j] < a[i][j])
		low_value = maxLength(low, j) + 1;
	else
		low_value = 0;

	int max1 = max(high_value, low_value);
	int max2 = max(left_value, right_value);
	return max(max1, max2);
}

int main()
{
	while (cin >> r >> c)
	{
		//初始化矩阵
		for (int i = 0; i < r; i++)
			for (int j = 0; j < c; j++)
				cin >> a[i][j];
		//计算每一个位置的最大长度
		for (int i = 0; i < r; i++)
			for (int j = 0; j < c; j++)
				result[i][j] = maxLength(i, j);
		//寻找所有位置中最大的长度
		int maxLen = 0;
		for (int i = 0; i < r; i++)
		{
			for (int j = 0; j < c; j++)
				if (result[i][j] > maxLen)
					maxLen = result[i][j];
		}
		cout << maxLen + 1 << endl;
	}
	
	system("pause");
	return 0;
}