struct Info {
    k: usize,
    c: i64,
    v: Vec<(usize, i64)>,
}

struct Input {
    n: usize,
    m: i64,
    info: Vec<Info>,
}

fn main() {
    let Input { n, m, info } = Input::read(std::io::stdin().lock());
    assert!(matches!(n, 1..=100));
    assert!(matches!(m, 0..=1_000_000_000));
    assert_eq!(n, info.len());
    for (i, Info { k, c, v }) in info.iter().enumerate() {
        assert!(*k < n);
        assert!(matches!(c, 0..=1_000_000_000));
        assert_eq!(*k, v.len());
        for (a, b) in v {
            assert!(*a < n);
            assert!(*a != i);
            assert!(matches!(b, 0..=1_000_000_000));
        }
        assert!(v.windows(2).all(|x| x[0].0 < x[1].0));
    }
    let mut ans = 0;
    for i in 0i64..1 << n {
        let mut tmp = m * i.count_ones() as i64;
        for (j, Info { c, .. }) in info.iter().enumerate() {
            if i >> j & 1 == 1 {
                tmp -= c;
            }
        }
        for (j, Info { v, .. }) in info.iter().enumerate() {
            if i >> j & 1 == 1 {
                for (a, b) in v {
                    if i >> a & 1 == 1 {
                        tmp += b;
                    }
                }
            }
        }
        ans = ans.max(tmp);
    }
    println!("{}", ans);
}

impl Input {
    fn read<T: std::io::BufRead>(mut input: T) -> Input {
        let (n, m) = {
            let mut buffer = String::new();
            input.read_line(&mut buffer).unwrap();
            match &split(&buffer).unwrap()[..] {
                [n, m] => (n.parse().unwrap(), m.parse().unwrap()),
                _ => panic!("input format error: N M"),
            }
        };
        let info = {
            let mut info = Vec::with_capacity(n);
            for _ in 0..n {
                let mut buffer = String::new();
                input.read_line(&mut buffer).unwrap();
                let (k, c) = match &split(&buffer).unwrap()[..] {
                    [k, c] => (k.parse().unwrap(), c.parse().unwrap()),
                    _ => panic!("input format error: k C"),
                };
                let v = if k == 0 {
                    Vec::new()
                } else {
                    let mut a = String::new();
                    input.read_line(&mut a).unwrap();
                    let a = split(&a).unwrap();
                    let mut b = String::new();
                    input.read_line(&mut b).unwrap();
                    let b = split(&b).unwrap();
                    let v = a
                        .iter()
                        .zip(&b)
                        .map(|(x, y)| (x.parse::<usize>().unwrap() - 1, y.parse().unwrap()))
                        .collect();
                    v
                };
                info.push(Info { k: k, c: c, v: v });
            }
            info
        };
        Input {
            n: n,
            m: m,
            info: info,
        }
    }
}

fn split(s: &str) -> Option<Vec<&str>> {
    enum State {
        Word(usize),
        Space,
        End,
    }
    let mut state = State::Word(0);
    let mut ret = Vec::new();
    for (i, c) in s.char_indices() {
        let prev = match state {
            State::End => return None,
            State::Word(i) => i,
            State::Space => {
                state = State::Word(i);
                i
            }
        };
        if c == ' ' || c == '\n' {
            ret.push(&s[prev..i]);
            state = if c == ' ' { State::Space } else { State::End };
        }
    }
    matches!(state, State::End).then(|| ret)
}