#include<iostream>
#include<vector>
#include<array>
#include<random>
#include<queue>
#include<algorithm>
#include<cmath>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef unsigned int ui;
typedef pair<int, int> pii;
void solve()
{
	int n, k;
	cin >> n >> k;
	vector<vector<int>>dp(n + 1, vector<int>(k + 1));
	vector<array<int, 11>>v(n + 1);
	for (int i = 1; i <= n; i++)
	{
		cin >> v[i][0];
		for (int j = 1; j <= v[i][0]; j++)
		{
			cin >> v[i][j];
		}
	}
	for (int i = 1; i <= n; i++)
	{
		for (int j = 0; j <= k; j++)
		{
			if (j + v[i][0] <= k)
			{
				dp[i][j + v[i][0]] = max({ dp[i][j + v[i][0]],dp[i - 1][j + v[i][0]], dp[i - 1][j] + v[i][v[i][0]] });
			}
			else
			{
				dp[i][k] = max({ dp[i - 1][k], dp[i - 1][j] + v[i][k - j],dp[i][k] });
			}
		}
	}
	int ans = 0;
	if(n==3000)
	for (int i = 1; i <= n; i++)
	{
		cout << dp[i][k] << endl;
	}
	cout << ans << endl;
}
void speed()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
}
int main()
{
	speed();
	int t;
	//cin >> t;
	t = 1;
	while (t--)
	{
		solve();
	}
	return 0;
}