#include <iostream>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <ctime>
#include <cstring>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <bitset>
#include <numeric>
#include <utility>
#include <iomanip>
#include <algorithm>
#include <functional>
#include <unordered_map>
using namespace std;

#define REP(i, s) for (int i = 0; i < s; ++i)
#define ALL(v) (v.begin(), v.end())
#define COUT(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << endl
#define EACH(i, s) for (__typeof__((s).begin()) i = (s).begin(); i != (s).end(); ++i)

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<class T1, class T2> ostream& operator << (ostream &s, pair<T1,T2> P)
{ return s << '<' << P.first << ", " << P.second << '>'; }
template<class T> ostream& operator << (ostream &s, vector<T> P)
{ for (int i = 0; i < P.size(); ++i) { if (i > 0) { s << " "; } s << P[i]; } return s; }
template<class T> ostream& operator << (ostream &s, vector<vector<T> > P)
{ for (int i = 0; i < P.size(); ++i) { s << endl << P[i]; } return s << endl; }
template<class T> ostream& operator << (ostream &s, set<T> P)
{ EACH(it, P) { s << "<" << *it << "> "; } return s << endl; }
template<class T1, class T2> ostream& operator << (ostream &s, map<T1,T2> P)
{ EACH(it, P) { s << "<" << it->first << "->" << it->second << "> "; } return s << endl; }



typedef vector<vector<int> > Graph;

vector<int> Prev;
pair<int,int> DiameterDFS(const vector<vector<int> > &G, int v, int p) {
    pair<int,int> res(v, 0);
    for (int i = 0; i < (int)G[v].size(); ++i) {
        if (G[v][i] == p) continue;
        pair<int,int> tmp = DiameterDFS(G, G[v][i], v);
        tmp.second++;
        if (tmp.second > res.second) {
            res = tmp;
            Prev[G[v][i]] = v;
        }
    }
    return res;
}

vector<int> Diameter(const vector<vector<int> > &G) {
    Prev = vector<int>((int)G.size(), -1);
    pair<int,int> leaf = DiameterDFS(G, 0, -1);
    Prev = vector<int>((int)G.size(), -1);
    pair<int,int> t = DiameterDFS(G, leaf.first, -1);
    vector<int> res;
    int cur = t.first;
    while (cur != -1) {
        res.push_back(cur);
        cur = Prev[cur];
    }
    return res;
}

int N;

int main() {
    while (cin >> N) {
        vector<vector<int> > G(N);
        for (int i = 0; i < N-1; ++i) {
            int u, v;
            cin >> u >> v;
            --u, --v;
            G[u].push_back(v);
            G[v].push_back(u);
        }
        
        vector<int> diameter = Diameter(G);
        
        int sum = (int)diameter.size();
        for (int i = 1; i < (int)diameter.size() - 1; ++i) {
            sum += (int)G[diameter[i]].size() - 2;
        }
        if (sum != N) {
            cout << -1 << endl;
            continue;
        }
        
        vector<int> alt1, alt2;
        int iter = 1;
        alt1.push_back(iter++);
        for (int i = 1; i < diameter.size(); ++i) {
            int deg = (int)G[diameter[i]].size();
            for (int j = 0; j < deg-2; ++j) {
                alt1.push_back(iter + j + 1);
            }
            alt1.push_back(iter);
            iter += deg - 1;
        }
        //COUT(alt1);
        
        reverse(diameter.begin(), diameter.end());
        iter = 1;
        alt2.push_back(iter++);
        for (int i = 1; i < diameter.size(); ++i) {
            int deg = (int)G[diameter[i]].size();
            for (int j = 0; j < deg-2; ++j) {
                alt2.push_back(iter + j + 1);
            }
            alt2.push_back(iter);
            iter += deg - 1;
        }
        
        if (alt1 > alt2) swap(alt1, alt2);
        for (int i = 0; i < alt1.size(); ++i) {
            cout << alt1[i];
            if (i != (int)alt1.size()-1) cout << " ";
        }
        cout << endl;
    }
}

























Measured memory_bytes: 16120