1088

/*
DP

好题，再次回顾此题，感慨颇多
*/

// include file
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cctype>
#include <ctime>

#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <bitset>

#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <set>
#include <list>
#include <functional>

using namespace std;

// typedef
typedef long long LL;
typedef unsigned long long ULL;

// 
#define read freopen("in.txt","r",stdin)
#define write freopen("out.txt","w",stdout)
#define FORi(a,b,c) for(int i=(a);i<(b);i+=c)
#define FORj(a,b,c) for(int j=(a);j<(b);j+=c)
#define FORk(a,b,c) for(int k=(a);k<(b);k+=c)
#define FORp(a,b,c) for(int p=(a);p<(b);p+=c)
#define FORii(a,b,c) for(int ii=(a);ii<(b);ii+=c)
#define FORjj(a,b,c) for(int jj=(a);jj<(b);jj+=c)
#define FORkk(a,b,c) for(int kk=(a);kk<(b);kk+=c)

#define FF(i,a)    for(int i=0;i<(a);i++)
#define FFD(i,a)   for(int i=(a)-1;i>=0;i--)

#define Z(a) (a<<1)
#define Y(a) (a>>1)

const double eps = 1e-6;
const double INFf = 1e100;
const int INFi = 1000000000;
const LL INFll = (LL)1<<62;
const double Pi = acos(-1.0);

template<class T> inline T sqr(T a){return a*a;}
template<class T> inline T TMAX(T x,T y)
{
	if(x>y) return x;
	return y;
}
template<class T> inline T TMIN(T x,T y)
{
	if(x<y) return x;
	return y;
}
template<class T> inline void SWAP(T &x,T &y)
{
	T t = x;
	x = y;
	y = t;
}
template<class T> inline T MMAX(T x,T y,T z)
{
	return TMAX(TMAX(x,y),z);
}
template<class T> inline T MMIN(T x,T y,T z)
{
	return TMIN(TMIN(x,y),z);
}


// code begin
int R,C;
int mp[110][110];
int DP[110][110];
int dir[4][2]={1,0,0,1,-1,0,0,-1};
int ans,r,c;
int DFS(int i,int j)
{
	if(DP[i][j]) return DP[i][j];
	FORk(0,4,1)
	{
		r = i+dir[k][0];
		c = j+dir[k][1];
		if( r>=1 && r<=R && c>=1 && c<=C && mp[r][c]>mp[i][j])
		{
			DP[i][j] = TMAX(DP[i][j],DFS(r,c));
		}
	}
	return DP[i][j] = DP[i][j]+1;
}
int getnext()
{
	char c;
	do
	{
		c = getchar();
	}while( c<'0' || c>'9');
	int ans = 0;
	do
	{
		ans = ans*10+c-'0';
		c = getchar();
	}while( c>='0' && c<='9');
	return ans;
}
int main()
{
	read;
	write;
	while(scanf("%d %d",&R,&C)==2)
	{
		FORi(1,R+1,1)
		{
			FORj(1,C+1,1)
			{
				mp[i][j] = getnext();
				//scanf("%d",&mp[i][j]);
				DP[i][j]= 0;
			}
		}
		ans = 0;
		FORi(1,R+1,1)
		{
			FORj(1,C+1,1)
			{
				if(!DP[i][j]) ans = TMAX(ans,DFS(i,j));
				else ans = TMAX(ans,DP[i][j]);
			}
		}
		printf("%d\n",ans);
	}
	return 0;
}