import java.util.Scanner;

/**
 * Created by Coder on 25.11.2014.
 */
public class FinalStandings1100_ {
    public static void main(String[] args) {
        Scanner x = new Scanner(System.in);
        int n = x.nextInt();
        int a[][] = new int[n][2];
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < 2; j++) {
                a[i][j] = x.nextInt();
            }
        }
        int k = 1;
        int d = 0
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n - 1; j++) {
                if (a[j][k] < a[j + 1][k]) {
                    int v = a[j][d];
                    a[j][d] = a[j + 1][d];
                    a[j + 1][d] = v;
                    int c = a[j][k];
                    a[j][k] = a[j + 1][k];
                    a[j + 1][k] = c;
                }
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < 2; j++) {
                System.out.print(a[i][j] + " ");
            }
            System.out.println();
        }
    }
}