/* Problem URL: https://codeforces.com/gym/105535/problem/E */ #include using namespace std; #define V vector #define rmin(a, b) a = min(a, b) #define rmax(a, b) a = max(a, b) #define rep(i, lim) for (int i = 0; i < (lim); i++) #define nrep(i, s, lim) for (int i = s; i < (lim); i++) #define repv(i, v) for (auto &i : (v)) #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; } #define sortv(v) sort(v.begin(), v.end()) #define all(v) (v).begin(), (v).end() using vi = vector; using vvi = vector; using vvvi = vector; using vvvvi = vector; using ll = long long; using vl = vector; using vvl = vector; using vvvl = vector; using vvvvl = vector; template auto operator<<(ostream &os, const vector &vec)->ostream& { os << vec[0]; for (size_t i = 1; i < vec.size(); i++) { os << ' ' << vec[i]; } os << '\n'; return os; } template auto operator>>(istream &is, vector &vec)->istream& { for (auto &i : vec) { is >> i; } return is; } template auto operator<<(ostream &os, const vector> &vec)->ostream& { for (auto &i : vec) { os << i[0]; for (size_t j = 1; j < i.size(); j++) { os << ' ' << i[j]; } os << '\n'; } return os; } template auto operator>>(istream &is, vector> &vec)->istream& { for (auto &i : vec) { for (auto &j : i) { is >> j; } } return is; } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int n; cin >> n; vi fds(n); cin >> fds; vvi graph(n); nrep(i, 1, n) { int a, b; cin >> a >> b; a--, b--; graph[a].push_back(b); graph[b].push_back(a); } vi ans; int total = 0; function dfs = [&](int i, int p) { fds[i]--; total++; ans.push_back(i + 1); repv(j, graph[i]) { if (j == p) { continue; } if (!dfs(j, i) || fds[i] == 0) { return false; } total++; fds[i]--; ans.push_back(i + 1); while (fds[j] > 0) { if (fds[i] == 0) { return false; } ans.push_back(j + 1); ans.push_back(i + 1); fds[i]--; fds[j]--; total += 2; } } return true; }; fds[0]++; int check = accumulate(all(fds), 0); if (!dfs(0, 0) || total != check) { cout << "0\n"; return 0; } cout << ans; }