Problem: We had a really tough time generating tests for problem D. In order to prepare strong tests, we had to solve the following problem.

Given an undirected labeled tree consisting of n vertices, find a set of segments such that:

  1. both endpoints of each segment are integers from 1 to 2n, and each integer from 1 to 2n should appear as an endpoint of exactly one segment; 
  2. all segments are non-degenerate; 
  3. for each pair (i, j) such that i ≠ j, i ∈ [1, n] and j ∈ [1, n], the vertices i and j are connected with an edge if and only if the segments i and j intersect, but neither segment i is fully contained in segment j, nor segment j is fully contained in segment i. 



Can you solve this problem too?

Input

The first line contains one integer n (1 ≤ n ≤ 5 ⋅ 10^5) — the number of vertices in the tree.

Then n - 1 lines follow, each containing two integers x_i and y_i (1 ≤ x_i, y_i ≤ n, x_i ≠ y_i) denoting the endpoints of the i-th edge.

It is guaranteed that the given graph is a tree.

Output

Print n pairs of integers, the i-th pair should contain two integers l_i and r_i (1 ≤ l_i < r_i ≤ 2n) — the endpoints of the i-th segment. All 2n integers you print should be unique.

It is guaranteed that the answer always exists.

Examples

Input


6
1 2
1 3
3 4
3 5
2 6


Output


9 12
7 10
3 11
1 5
2 4
6 8


Input


1


Output


1 2

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;

/*
───────────────■■■─────────────────────────
──█▄─▄█─▄▀▀▀▄─█──▄█─────█──▄▀─▄▀▀▀▄─▀▀█▀▀──
──█─▀─█─█───█─█─█─█─────█■█───█───█───█────
──█───█─▀▄▄▄▀─█▀──█─────█──▀▄─▀▄▄▄▀───█────
───────────────────────────────────────────
*/

public class Main {

    static FastReader in;
    static PrintWriter out;
    static Random rand = new Random();
    static final int INF = (int) (1e9);
    static final int MOD = (int) (1e9 + 7);
    static final int N = (int) (1e6 + 6);
    static int n;
    static ArrayList<Integer>[] g;
    static int[] size;
    static int[][] segs;

    static void dfs1(int v, int par) {
        size[v] = 1;
        for (int u : g[v]) {
            if (u != par) {
                dfs1(u, v);
                size[v] += size[u];
            }
        }
    }

    static void dfs2(int v, int par, int x) {
        int r = x + g[v].size() - 1;
        if (par == -1) r++;
        int i = r - 1, j = r + 1;
        for (int u : g[v]) {
            if (u != par) {
                segs[u][0] = i;
                dfs2(u, v, j);
                i--;
                j += size[u] * 2 - 1;
            }
        }
        segs[v][1] = r;
    }

    static void solve() {
        n = in.nextInt();

        g = new ArrayList[n];
        Arrays.setAll(g, i -> new ArrayList<>());
        for (int i = 0; i < n - 1; i++) {
            int x = in.nextInt() - 1;
            int y = in.nextInt() - 1;
            g[x].add(y);
            g[y].add(x);
        }

        size = new int[n];
        dfs1(0, -1);

        segs = new int[n][2];
        segs[0][0] = 1;
        dfs2(0, -1, 2);

        for (int i = 0; i < n; i++) {
            out.println(segs[i][0] + " " + segs[i][1]);
        }
    }

    public static void main(String[] args) throws FileNotFoundException {
        in = new FastReader(System.in);
//        in = new FastReader(new FileInputStream("input.txt"));
        out = new PrintWriter(System.out);
//        out = new PrintWriter(new FileOutputStream("output.txt"));


        int q = 1;

        while (q-- > 0) {
            solve();
        }

        out.close();
    }

    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        FastReader(InputStream is) {
            br = new BufferedReader(new InputStreamReader(is));
        }

        Integer nextInt() {
            return Integer.parseInt(next());
        }

        Long nextLong() {
            return Long.parseLong(next());
        }

        Double nextDouble() {
            return Double.parseDouble(next());
        }

        String next() {
            while (st == null || !st.hasMoreTokens()) {
                st = new StringTokenizer(nextLine());
            }
            return st.nextToken();
        }

        String nextLine() {
            String s = "";
            try {
                s = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return s;
        }
    }
}