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| #include <bits/stdc++.h>
#pragma optimization_level 3 #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3") #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx") #pragma GCC optimize("Ofast") #pragma GCC target("avx,avx2,fma") #pragma GCC optimization ("unroll-loops")
struct PairHash { inline std::size_t operator()(const std::pair<int, int> &v) const { return v.first * 31 + v.second; } };
#define MAX_N 1010101 #define INF 987654321 #define EPS 1e-9 #define ll long long #define pll pair<ll, ll> #define vpll vector<pll> #define vall3 vector<array<ll,3>> #define all3 array<ll,3> #define all5 array<ll,5> #define vall5 vector<all5> #define vll vector<ll> #define vi vector<int> #define vs vector<string> #define usll unordered_set<ll> #define uspll unordered_set<pll, PairHash> #define umll unordered_map<ll,ll> #define vvs vector<vs> #define vvll vector<vll> #define all(a) begin(a), end(a) #define rall(a) rbegin(a), rend(a)
ll __gcd(ll x, ll y) { return !y ? x : __gcd(y, x % y); }
using namespace std; void dfs(ll u, ll par, vpll& res, vvll& adj, ll& leaf) { if(adj[u].size() == 1) { if(par != -1) { res[u] = {leaf, leaf}; leaf++; } else { dfs(adj[u][0], u, res, adj, leaf); res[u] = res[adj[u][0]]; } } else { for(auto& v : adj[u]) { if(v == par) continue; dfs(v, u, res, adj, leaf); res[u].first = min(res[u].first, res[v].first); res[u].second = max(res[u].second, res[v].second); } } } vpll solve(vpll& A) { ll n = A.size() + 1, leaf = 1; vpll res(n, {INT_MAX, INT_MIN}); vvll adj(n); for(auto& [u, v] : A) { adj[u-1].push_back(v-1); adj[v-1].push_back(u-1); } dfs(0,-1,res,adj, leaf); return res; }
int main() { ios_base::sync_with_stdio(0); ios::sync_with_stdio(0); cin.tie(0); ll tc = 1; for (ll i = 1; i <= tc; i++) { ll n; cin>>n; vpll E(n - 1); for(ll j = 0; j < n - 1; j++) cin>>E[j].first>>E[j].second; auto res = solve(E); for(auto& [l, r] : res) cout<<l<<' '<<r<<endl; } return 0; }
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