#include <bits/stdc++.h>
using namespace std;

int n,k,val[3005],ans,w[3005][13],dp[3005][3005][2];

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin>>n>>k;
    for (int i=1; i<=n; ++i) {
        cin>>val[i];
        for (int j=1; j<=val[i]; ++j) cin>>w[i][j];
    }
    
    for (int i=1; i<=n; ++i) {
        for (int use=1; use>=0; --use) {
            for (int j=val[i]; j<=k; ++j) dp[i][j][use]=max(dp[i-1][j][use],dp[i-1][j-val[i]][use]+w[i][val[i]]);
            if (use==0) {
                for (int lst=1; lst<val[i]; ++lst) {
                    for (int j=lst; j<=k; ++j) dp[i][j][1]=max(dp[i][j][1],dp[i-1][j-lst][0]+w[i][lst]);
                }
            }
        }
    }
    
    for (int j=0; j<=k; ++j) ans=max({ans,dp[n][j][0],dp[n][j][1]});
    cout<<ans;
}