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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
const int mod = 1000000007;
int n;
vector<int> G[500010];
pair<int, int> ans[500010];
int dg[500010];
int Dfs(int ed, int p, int pre) {
  int new_ed = ed;
  int num = 0;
  for (int i = 0; i <= ((int)(G[p]).size()) - 1; ++i) {
    int v = G[p][i];
    if (v == pre) continue;
    num++;
    ans[v] = make_pair(new_ed - num, ed + dg[v]);
    ed = Dfs(ed + dg[v], v, p);
  }
  return ed;
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n - 1; ++i) {
    int a, b;
    scanf("%d %d", &a, &b);
    dg[a]++;
    dg[b]++;
    G[a].push_back(b);
    G[b].push_back(a);
  }
  ans[1] = make_pair(1, dg[1] + 2);
  Dfs(dg[1] + 2, 1, -1);
  for (int i = 1; i <= n; ++i) {
    printf("%d %d\n", ans[i].first, ans[i].second);
  }
  return 0;
}