use std::{collections::BTreeMap, io::Read};

fn main() {
	let mut s = String::new();
	std::io::stdin().read_to_string(&mut s).ok();
	let v: Vec<_> = s.split_whitespace().skip(2).collect();
	let mut h = BTreeMap::new();
	for x in v.chunks(2) {
		h.insert(x[0], x[1]);
	}
	for (k, v) in h.iter() {
		println!("{} {}", k, v)
	}
}