結果
| 問題 | No.1976 Cut then Connect |
| ユーザー |
👑  tute7627
|
| 提出日時 | 2022-06-10 22:43:19 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 207 ms / 2,000 ms |
| コード長 | 9,368 bytes |
| コンパイル時間 | 2,564 ms |
| コンパイル使用メモリ | 217,248 KB |
| 最終ジャッジ日時 | 2025-01-29 20:09:48 |
|
ジャッジサーバーID （参考情報） |
judge3 / judge2 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 31 |
ソースコード
//#define _GLIBCXX_DEBUG#include<bits/stdc++.h>using namespace std;#define endl '\n'#define lfs cout<<fixed<<setprecision(10)#define ALL(a) (a).begin(),(a).end()#define ALLR(a) (a).rbegin(),(a).rend()#define UNIQUE(a) (a).erase(unique((a).begin(),(a).end()),(a).end())#define spa << " " <<#define fi first#define se second#define MP make_pair#define MT make_tuple#define PB push_back#define EB emplace_back#define rep(i,n,m) for(ll i = (n); i < (ll)(m); i++)#define rrep(i,n,m) for(ll i = (ll)(m) - 1; i >= (ll)(n); i--)using ll = long long;using ld = long double;const ll MOD1 = 1e9+7;const ll MOD9 = 998244353;const ll INF = 1e18;using P = pair<ll, ll>;template<typename T> using PQ = priority_queue<T>;template<typename T> using QP = priority_queue<T,vector<T>,greater<T>>;template<typename T1, typename T2>bool chmin(T1 &a,T2 b){if(a>b){a=b;return true;}else return false;}template<typename T1, typename T2>bool chmax(T1 &a,T2 b){if(a<b){a=b;return true;}else return false;}ll median(ll a,ll b, ll c){return a+b+c-max({a,b,c})-min({a,b,c});}void ans1(bool x){if(x) cout<<"Yes"<<endl;else cout<<"No"<<endl;}void ans2(bool x){if(x) cout<<"YES"<<endl;else cout<<"NO"<<endl;}void ans3(bool x){if(x) cout<<"Yay!"<<endl;else cout<<":("<<endl;}template<typename T1,typename T2>void ans(bool x,T1 y,T2 z){if(x)cout<<y<<endl;else cout<<z<<endl;}template<typename T1,typename T2,typename T3>void anss(T1 x,T2 y,T3 z){ans(x!=y,x,z);};template<typename T>void debug(const T &v,ll h,ll w,string sv=" "){for(ll i=0;i<h;i++){cout<<v[i][0];for(ll j=1;j<w;j++)cout<<sv<<v[i][j];cout<<endl;}};template<typename T>void debug(const T &v,ll n,string sv=" "){if(n!=0)cout<<v[0];for(ll i=1;i<n;i++)cout<<sv<<v[i];cout<<endl;};template<typename T>void debug(const vector<T>&v){debug(v,v.size());}template<typename T>void debug(const vector<vector<T>>&v){for(auto &vv:v)debug(vv,vv.size());}template<typename T>void debug(stack<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}template<typename T>void debug(queue<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop();}cout<<endl;}template<typename T>void debug(deque<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop_front();}cout<<endl;}template<typename T>void debug(PQ<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}template<typename T>void debug(QP<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;}template<typename T>void debug(const set<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;}template<typename T>void debug(const multiset<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;}template<typename T,size_t size>void debug(const array<T, size> &a){for(auto z:a)cout<<z<<" ";cout<<endl;}template<typename T,typename V>void debug(const map<T,V>&v){for(auto z:v)cout<<"["<<z.first<<"]="<<z.second<<",";cout<<endl;}template<typename T>vector<vector<T>>vec(ll x, ll y, T w){vector<vector<T>>v(x,vector<T>(y,w));return v;}ll gcd(ll x,ll y){ll r;while(y!=0&&(r=x%y)!=0){x=y;y=r;}return y==0?x:y;}vector<ll>dx={1,-1,0,0,1,1,-1,-1};vector<ll>dy={0,0,1,-1,1,-1,1,-1};template<typename T>vector<T> make_v(size_t a,T b){return vector<T>(a,b);}template<typename... Ts>auto make_v(size_t a,Ts... ts){return vector<decltype(make_v(ts...))>(a,make_v(ts...));}template<typename T1, typename T2>ostream &operator<<(ostream &os, const pair<T1, T2>&p){return os << p.first << " " << p.second;}template<typename T>ostream &operator<<(ostream &os, const vector<T> &v){for(auto &z:v)os << z << " ";cout<<"|"; return os;}template<typename T>void rearrange(vector<int>&ord, vector<T>&v){auto tmp = v;for(int i=0;i<tmp.size();i++)v[i] = tmp[ord[i]];}template<typename Head, typename... Tail>void rearrange(vector<int>&ord,Head&& head, Tail&&... tail){rearrange(ord, head);rearrange(ord, tail...);}template<typename T> vector<int> ascend(const vector<T>&v){vector<int>ord(v.size());iota(ord.begin(),ord.end(),0);sort(ord.begin(),ord.end(),[&](int i,int j){return v[i]<v[j];});return ord;}template<typename T> vector<int> descend(const vector<T>&v){vector<int>ord(v.size());iota(ord.begin(),ord.end(),0);sort(ord.begin(),ord.end(),[&](int i,int j){return v[i]>v[j];});return ord;}template<typename T> vector<T> inv_perm(const vector<T>&ord){vector<T>inv(ord.size());for(int i=0;i<ord.size();i++)inv[ord[i]] = i;return inv;}ll FLOOR(ll n,ll div){assert(div>0);return n>=0?n/div:(n-div+1)/div;}ll CEIL(ll n,ll div){assert(div>0);return n>=0?(n+div-1)/div:n/div;}ll digitsum(ll n){ll ret=0;while(n){ret+=n%10;n/=10;}return ret;}ll modulo(ll n,ll d){return (n%d+d)%d;};template<typename T>T min(const vector<T>&v){return *min_element(v.begin(),v.end());}template<typename T>T max(const vector<T>&v){return *max_element(v.begin(),v.end());}template<typename T>T acc(const vector<T>&v){return accumulate(v.begin(),v.end(),T(0));};template<typename T>T reverse(const T &v){return T(v.rbegin(),v.rend());};//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());int popcount(ll x){return __builtin_popcountll(x);};int poplow(ll x){return __builtin_ctzll(x);};int pophigh(ll x){return 63 - __builtin_clzll(x);};template<typename T>T poll(queue<T> &q){auto ret=q.front();q.pop();return ret;};template<typename T>T poll(priority_queue<T> &q){auto ret=q.top();q.pop();return ret;};template<typename T>T poll(QP<T> &q){auto ret=q.top();q.pop();return ret;};template<typename T>T poll(stack<T> &s){auto ret=s.top();s.pop();return ret;};ll MULT(ll x,ll y){if(LLONG_MAX/x<=y)return LLONG_MAX;return x*y;}ll POW2(ll x, ll k){ll ret=1,mul=x;while(k){if(mul==LLONG_MAX)return LLONG_MAX;if(k&1)ret=MULT(ret,mul);mul=MULT(mul,mul);k>>=1;}return ret;}ll POW(ll x, ll k){ll ret=1;for(int i=0;i<k;i++){if(LLONG_MAX/x<=ret)return LLONG_MAX;ret*=x;}return ret;}template< typename T = int >struct edge {int to;T cost;int id;edge():id(-1){};edge(int to, T cost = 1, int id = -1):to(to), cost(cost), id(id){}operator int() const { return to; }};template<typename T>using Graph = vector<vector<edge<T>>>;template<typename T>Graph<T>revgraph(const Graph<T> &g){Graph<T>ret(g.size());for(int i=0;i<g.size();i++){for(auto e:g[i]){int to = e.to;e.to = i;ret[to].push_back(e);}}return ret;}template<typename T>Graph<T> readGraph(int n,int m,int indexed=1,bool directed=false,bool weighted=false){Graph<T> ret(n);for(int es = 0; es < m; es++){int u,v;T w=1;cin>>u>>v;u-=indexed,v-=indexed;if(weighted)cin>>w;ret[u].emplace_back(v,w,es);if(!directed)ret[v].emplace_back(u,w,es);}return ret;}template<typename T>Graph<T> readParent(int n,int indexed=1,bool directed=true){Graph<T>ret(n);for(int i=1;i<n;i++){int p;cin>>p;p-=indexed;ret[p].emplace_back(i);if(!directed)ret[i].emplace_back(p);}return ret;}template< typename sum_t, typename key_t >struct ReRooting {struct Edge {int to;key_t data;sum_t dp, ndp;};using F = function< sum_t(sum_t, sum_t) >;using G = function< sum_t(sum_t, key_t) >;vector< vector< Edge > > g;vector< sum_t > subdp, dp;vector< sum_t > init;const sum_t ident;const F f;const G gg;ReRooting(int V, const F f, const G g, const sum_t &ident): g(V), f(f), gg(g), ident(ident), subdp(V, ident), dp(V, ident), init(V, ident) {}void add_edge(int u, int v, const key_t &d) {g[u].emplace_back((Edge) {v, d, ident, ident});g[v].emplace_back((Edge) {u, d, ident, ident});}void add_edge_bi(int u, int v, const key_t &d, const key_t &e) {g[u].emplace_back((Edge) {v, d, ident, ident});g[v].emplace_back((Edge) {u, e, ident, ident});}void set(int idx, sum_t s){subdp[idx] = s;init[idx] = s;}void dfs_sub(int idx, int par) {for(auto &e : g[idx]) {if(e.to == par) continue;dfs_sub(e.to, idx);subdp[idx] = f(subdp[idx], gg(subdp[e.to], e.data));}}void dfs_all(int idx, int par, const sum_t &top) {sum_t buff{init[idx]};for(int i = 0; i < (int) g[idx].size(); i++) {auto &e = g[idx][i];e.ndp = buff;e.dp = gg(par == e.to ? top : subdp[e.to], e.data);buff = f(buff, e.dp);}dp[idx] = buff;buff = ident;for(int i = (int) g[idx].size() - 1; i >= 0; i--) {auto &e = g[idx][i];if(e.to != par) dfs_all(e.to, idx, f(e.ndp, buff));e.ndp = f(e.ndp, buff);buff = f(buff, e.dp);}}vector< sum_t > build() {dfs_sub(0, -1);dfs_all(0, -1, ident);return dp;}};int main(){cin.tie(nullptr);ios_base::sync_with_stdio(false);ll res=0,buf=0;bool judge = true;ll n;cin>>n;auto f1=[&](P x,P y)->P{return MP(max({x.fi,y.fi,x.se+y.se}),max(x.se,y.se));};auto f2=[&](P x,ll w)->P{return MP(x.fi,x.se+1);};ReRooting<P,ll>rer(n,f1,f2,MP(0,0));rep(i,0,n-1){ll u,v;cin>>u>>v;u--;v--;rer.add_edge(u,v,1);}rer.build();map<P,P>mp;rep(i,0,n){for(auto e:rer.g[i]){auto k=MP(min<ll>(i,e.to),max<ll>(i,e.to));chmax(mp[k].fi,e.dp.fi);mp[k].se+=(e.dp.fi+1)/2;//cout<<k<<endl;}}res=INF;for(auto z:mp){//cout<<z<<endl;chmin(res,max(z.se.fi,z.se.se+1));}cout<<res<<endl;return 0;}