use std::io::Read;

fn run() {
    let mut s = String::new();
    std::io::stdin().read_to_string(&mut s).unwrap();
    let mut it = s.trim().split_whitespace();
    let n: usize = it.next().unwrap().parse().unwrap();
    let mut q = std::collections::VecDeque::new();
    for _ in 0..n {
        let p: usize = it.next().unwrap().parse().unwrap();
        let mut a: Vec<u32> = (0..p).map(|_| it.next().unwrap().parse().unwrap()).collect();
        a.sort();
        a.reverse();
        q.push_back(a);
    }
    let mut ans = String::new();
    while let Some(mut a) = q.pop_front() {
        if let Some(v) = a.pop() {
            ans.push_str(&format!("{} ", v));
            q.push_back(a);
        }
    }
    ans.pop();
    println!("{}", ans);
}

fn main() {
    run();
}