H

#define _CRT_SECURE_NO_DEPRECATE

#include <iostream>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>

using namespace std;

long long binpow(long long a, int n, long long p) {
	long long res = 1;
	while (n > 0) {
		if (n & 1)
			res = (res * a) % p;
		a = (a * a) % p;
		n >>= 1;
	}
	return res;
}

int main() {
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
	int n;
	cin >> n;
	vector<pair<int, pair<int, int> > > a(n);
	for (int i = 0; i < n; i++) {
		cin >> a[i].first >> a[i].second.second;
		a[i].second.first = i;
	}
	sort(a.begin(), a.end());
	for (int i = 0; i < n; i++) {
		cout << a[i].first << ' ' << a[i].second.second << endl;
	}
}