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;
vector<pair<int, int> > edges;
const int ms = 5e5 + 9;
vector<int> g[ms];
int n, right_most = 0;
void dfs(int u, int L = 0, int R = 0, int p = -1) {
  right_most = max(right_most, R);
  int siblings_size = g[u].size();
  int child_sizes = (p == -1) ? siblings_size : siblings_size - 1;
  edges[u - 1] = pair<int, int>(L, R);
  int l = R;
  for (auto v : g[u]) {
    if (v != p) {
      l--;
      int v_size = int(g[v].size()) - 1;
      dfs(v, l, right_most + 1 + v_size, u);
    }
  }
}
int main() {
  scanf("%d ", &n);
  edges.resize(n);
  for (int i = 0; i < n - 1; i++) {
    int u, v;
    scanf("%d %d", &u, &v);
    g[u].push_back(v);
    g[v].push_back(u);
  }
  dfs(1, 1, 1 + 1 + g[1].size(), -1);
  for (auto it : edges) {
    printf("%d %d\n", it.first, it.second);
  }
}