#include<bits/stdc++.h>

using namespace std;

typedef long long LL;

const int N = 1010;
const int M = 10;

int n, k;
int a[M][N], in[N], ans;
int h[N << 1], e[N << 1], ne[N << 1], cnt;

bool check(int x, int y) {
	for(int i = 1; i <= k; ++ i)
		if(a[i][x] >= a[i][y]) return 0;
	return 1;
}

void add(int u, int v) {
	e[++ cnt] = v, ne[cnt] = h[u], h[u] = cnt;
}

void dfs(int u, int sum) {
	ans = max(ans, sum);
	for(int i = h[u]; i; i = ne[i]) {
		int v = e[i];
		dfs(v, sum + 1);
	}
}

int main() {
	cin >> n >> k;
	for(int i = 1; i <= k; ++ i)
		for(int j = 1; j <= n; ++ j) {
			int x; cin >> x;
			a[i][x] = j;
		}
	for(int i = 1; i <= n; ++ i)
		for(int j = 1; j <= n; ++ j)
			if(check(i, j)) {
				add(i, j);
				++ in[j];
			}
	for(int i = 1; i <= n; ++ i)
		if(!in[i]) dfs(i, 1);
	cout << ans;
	return 0;
}