use std::io::Read;
use std::collections::VecDeque;

fn solve(count: usize, registers: &mut Vec<VecDeque<u32>>) {
    let mut result: Vec<u32> = vec![];
    while result.len() < count {
        registers.iter_mut()
            .filter(|r| !r.is_empty())
            .for_each(|r| {
                result.push(r.pop_front().unwrap());
            });
    }
    println!("{}", result.iter().map(|v| v.to_string()).collect::<Vec<String>>().join(" "));
}

fn main() {
    let mut all_data = String::new();
    std::io::stdin().read_to_string(&mut all_data).ok();
    let all_data: Vec<&str> = all_data.trim().split('\n').map(|s| s.trim()).collect();
    let n: u32 = all_data.iter().next().unwrap().parse::<u32>().unwrap();
    let mut registers: Vec<VecDeque<u32>> = all_data.iter().skip(1).take(n as usize)
        .map(|c| c.split_whitespace().skip(1).map(|v| v.parse::<u32>().unwrap()).collect::<VecDeque<u32>>())
        .filter(|l| !l.is_empty())
        .collect();
    let count = registers.iter().flatten().count();
    solve(count, &mut registers);
}