fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n = n.trim().parse::<usize>().unwrap();

    let mut max: usize = 0;
    let a = &mut vec![];
    for _ in 0..n {
        let mut line = String::new();
        std::io::stdin().read_line(&mut line).ok();
        let line: Vec<usize> = line.trim().split(" ")
                    .map(|x| x.parse::<usize>().unwrap())
                    .collect();
        max = std::cmp::max(max, line[0]);
        a.push(line);
    }
    for i in 1..=max{
        for j in 0..n {
            if let Some(p) = a[j].get(i) {
                print!("{:?} ", p);
            }
        }
    }
}