結果
| 問題 | No.1582 Vertexes vs Edges |
| コンテスト | |
| ユーザー |
 ryoku
|
| 提出日時 | 2026-07-23 17:56:38 |
| 言語 | C++23(gcc16) (gcc 16.1.0 + boost 1.90.0) |
| 結果 |
AC
|
| 実行時間 | 15 ms / 2,000 ms |
| + 372µs | |
| コード長 | 24,687 bytes |
| 記録 | |
| コンパイル時間 | 2,587 ms |
| コンパイル使用メモリ | 315,752 KB |
| 実行使用メモリ | 8,064 KB |
| 最終ジャッジ日時 | 2026-07-23 17:56:45 |
| 合計ジャッジ時間 | 5,466 ms |
|
ジャッジサーバーID （参考情報） |
judge3_0 / judge2_0 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 36 |
ソースコード
#line 1 "lib/template.hpp"
#ifdef TEMPLATE
#else
#define TEMPLATE
# pragma GCC optimize("O3")
using namespace std;
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <string>
#include <cstring>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <algorithm>
#include <numeric>
#include <cmath>
#include <climits>
#include <cassert>
#include <functional>
#include <iterator>
#include <utility>
#include <complex>
#include <bitset>
#include <chrono>
#include <random>
#include <limits>
#include <optional>
#include <variant>
#include <any>
#include <array>
#include <bit>
#include <compare>
#include <concepts>
#include <numbers>
#include <ranges>
#include <span>
#include <string_view>
#include <tuple>
#include <type_traits>
#include <version>
using uint=unsigned;
using ll=long long;
using ull=unsigned long long;
using ld=long double;
using pii=pair<int,int>;
using pll=pair<ll,ll>;
using i128=__int128;
template<class T>using vc=vector<T>;
template<class T>using vvc=vc<vc<T>>;
template<class T>using vvvc=vvc<vc<T>>;
template<class T>using smpq=priority_queue<T,vector<T>,greater<T>>;
template<class T>using bipq=priority_queue<T>;
#define rep(i,n) for(ll i=0;i<(ll)(n);i++)
#define REP(i,j,n) for(ll i=(j);i<(ll)(n);i++)
#define DREP(i,n,m) for(ll i=(n);i>=(m);i--)
#define drep(i,n) for(ll i=((n)-1);i>=0;i--)
#define rall(x) x.rbegin(),x.rend()
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define is insert
#define bg begin()
#define ed end()
#define all(x) x.begin(),x.end()
void scan(int&a) { cin >> a; }
void scan(ll&a) { cin >> a; }
void scan(string&a) { cin >> a; }
void scan(char&a) { cin >> a; }
void scan(uint&a) { cin >> a; }
void scan(ull&a) { cin >> a; }
void scan(bool&a) { cin >> a; }
void scan(ld&a){ cin>> a;}
template<class T> void scan(vector<T>&a) { for(auto&x:a) scan(x); }
void read() {}
template<class Head, class... Tail> void read(Head&head, Tail&... tail) { scan(head); read(tail...); }
#define INT(...) int __VA_ARGS__; read(__VA_ARGS__);
#define LL(...) ll __VA_ARGS__; read(__VA_ARGS__);
#define ULL(...) ull __VA_ARGS__; read(__VA_ARGS__);
#define STR(...) string __VA_ARGS__; read(__VA_ARGS__);
#define VC(type, name, ...) vector<type> name(__VA_ARGS__); read(name);
#define VVC(type, name, size, ...) vector<vector<type>> name(size, vector<type>(__VA_ARGS__)); read(name);
template<class T>void print(T a) { cout << a; }
template<class T> void print(vector<T>a) { for(int i=0;i<(int)a.size();i++){if(i)cout<<" ";print(a[i]);}cout<<endl;}
void PRT() { cout <<endl; return ; }
template<class T> void PRT(T a) { print(a); cout <<endl; return; }
template<class Head, class... Tail> void PRT(Head head, Tail ... tail) { print(head); cout << " "; PRT(tail...); return; }
template<class T,class F>
bool chmin(T &x, F y){
if(x>y){
x=y;
return true;
}
return false;
}
template<class T, class F>
bool chmax(T &x, F y){
if(x<y){
x=y;
return true;
}
return false;
}
template <typename T>
T floor(T a, T b) {
return a / b - (a % b && (a ^ b) < 0);
}
template <typename T>
T ceil(T x, T y) {
return floor(x + y - 1, y);
}
template <typename T>
T bmod(T x, T y) {
return x - y * floor(x, y);
}
template <typename T>
pair<T, T> divmod(T x, T y) {
T q = floor(x, y);
return {q, x - q * y};
}
void YesNo(bool b){
cout<<(b?"Yes":"No")<<endl;
}
void YESNO(bool b){
cout<<(b?"YES":"NO")<<endl;
}
void AliceBob(bool b){
cout<<(b?"Alice":"Bob")<<endl;
}
void TakahashiAoki(bool b){
cout<<(b?"Takahashi":"Aoki")<<endl;
}
void Yes(){
cout<<"Yes"<<endl;
}
void No(){
cout<<"No"<<endl;
}
vc<int>stovi(const string&s,const string&S){
vc<int>v(s.size());
rep(i,s.size()){
auto t=S.find(s[i]);
assert(t!=string::npos);
v[i]=t;
}
return v;
}
template<class T=ll>
T isqrt(T x){
T F=sqrtl(x);
while((F+1)*(F+1)<=x)F++;
while(F*F>x)F--;
return F;
}
template<class T>
vvc<T>trans(const vvc<T>&a){
assert(a.size()&&a[0].size());
vvc<T>b(a[0].size(),vc<T>(a.size()));
rep(i,a.size())rep(j,a[0].size()){
b[j][i]=a[i][j];
}
return b;
}
template<class T>
vc<string>trans(const vc<string>&a){
assert(a.size()&&a[0].size());
vc<string>b(a[0].size(),string(a.size(),0));
rep(i,a.size())rep(j,a[0].size()){
b[j][i]=a[i][j];
}
return b;
}
template<class T>
int popcount(T n){
return __builtin_popcountll(n);
}
template<class T,class L=ll>
L sum(vc<T>&a){
return accumulate(all(a),L(0));
}
template<class T>
vc<T>subset(T S){
vc<T>ans;
for(T x=S;x>0;x=(x-1)&S)ans.pb(x);
ans.pb(0);
return ans;
}
template<class T>
T max(vc<T>&a){
return *max_element(all(a));
}
template<class T>
T min(vc<T>&a){
return *min_element(all(a));
}
#ifndef COMPRESSER_STRUCT
#define COMPRESSER_STRUCT
template<class T>
struct Compresser{
vc<T>x;
Compresser(int n=0){x.reserve(n);}
Compresser(const vc<T>&xs){
x=xs;
}
void push(T p){built=false;x.pb(p);}
bool built=false;
void build(){
if(!chmax(built,1))return;
sort(all(x));
x.erase(unique(all(x)),x.end());
}
int find(T v){
build();
auto itr=lower_bound(all(x),v)-x.begin();
if(itr==x.size()||x[itr]!=v)return -1;
return itr;
}
int find_next(T v){
build();
return lower_bound(all(x),v)-x.begin();
}
int size(){
build();
return x.size();
}
T operator[](int i)const{
assert(0<=i&&i<x.size());
return x[i];
}
};
#endif
template<class T,class L=ll>
vc<L> presum(vc<T> &a){
vc<L> ret(a.size()+1);
rep(i,a.size())ret[i+1]=ret[i]+a[i];
return ret;
}
template<class T, class F>
vc<T> &operator+=(vc<T> &a,F b){
for (auto&v:a)v += b;
return a;
}
template<class T, class F>
vc<T> &operator-=(vc<T>&a,F b){
for (auto&v:a)v-=b;
return a;
}
template<class T, class F>
vc<T> &operator*=(vc<T>&a,F b){
for (auto&v:a)v*=b;
return a;
}
template<class T=ll>
constexpr T POW(T a,T b){
T res=1;
while(b){
if(b&1)res*=a;
a*=a;
b/=2;
}
return res;
}
constexpr ll ten(ll a){
return POW<ll>(10,a);
}
template<typename T>constexpr T inf=numeric_limits<T>::max()/2-1;
template<class T>
int tbit(T x){
using U=make_unsigned_t<T>;
U y=(U)x;
return y?(int)bit_width(y)-1:-1;
}
template<class T>
int lbit(T x){
using U=make_unsigned_t<T>;
U y=(U)x;
return y?(int)countr_zero(y):-1;
}
template<class T>
int tbit(T x,int p){
using U=make_unsigned_t<T>;
constexpr int W=numeric_limits<U>::digits;
U y=(U)x;
if(p<0)return -1;
if(p>=W-1)return tbit(y);
return tbit(y&((U(1)<<(p+1))-1));
}
template<class T>
int lbit(T x,int p){
using U=make_unsigned_t<T>;
constexpr int W=numeric_limits<U>::digits;
U y=(U)x;
if(p<0)return lbit(y);
if(p>=W)return -1;
return lbit(y&(~U(0)<<p));
}
istream& operator>>(istream&is,i128&x){
string s;is>>s;
x=0;
int i=0,neg=0;
if(s[0]=='-')neg=1,i=1;
for(;i<(int)s.size();i++)x=x*10+s[i]-'0';
if(neg)x=-x;
return is;
}
ostream& operator<<(ostream&os,i128 x){
if(x==0)return os<<0;
if(x<0)os<<"-";
using u128=__uint128_t;
u128 y=x<0?-(u128)x:(u128)x;
string s;
while(y)s.pb('0'+y%10),y/=10;
reverse(all(s));
return os<<s;
}
#define dbg(...) 1111
#ifdef LOCAL
#undef dbg
template<class T,class U>
ostream& operator<<(ostream&os,const pair<T,U>&p){
return os<<"("<<p.fi<<", "<<p.se<<")";
}
template<class T,size_t N>
ostream& operator<<(ostream&os,const array<T,N>&a){
os<<"[";
rep(i,N){
if(i)os<<", ";
os<<a[i];
}
return os<<"]";
}
template<class T>
ostream& operator<<(ostream&os,const vc<T>&a){
os<<"[";
rep(i,a.size()){
if(i)os<<", ";
os<<a[i];
}
return os<<"]";
}
template<class T>
ostream& operator<<(ostream&os,const deque<T>&a){
os<<"[";
rep(i,a.size()){
if(i)os<<", ";
os<<a[i];
}
return os<<"]";
}
template<class T>
ostream& operator<<(ostream&os,const set<T>&s){
os<<"{";
bool f=0;
for(auto&x:s){
if(f)os<<", ";
f=1;
os<<x;
}
return os<<"}";
}
template<class T>
ostream& operator<<(ostream&os,const multiset<T>&s){
os<<"{";
bool f=0;
for(auto&x:s){
if(f)os<<", ";
f=1;
os<<x;
}
return os<<"}";
}
template<class T>
ostream& operator<<(ostream&os,const unordered_set<T>&s){
os<<"{";
bool f=0;
for(auto&x:s){
if(f)os<<", ";
f=1;
os<<x;
}
return os<<"}";
}
template<class T,class U>
ostream& operator<<(ostream&os,const map<T,U>&m){
os<<"{";
bool f=0;
for(auto&x:m){
if(f)os<<", ";
f=1;
os<<x;
}
return os<<"}";
}
template<class T,class U>
ostream& operator<<(ostream&os,const unordered_map<T,U>&m){
os<<"{";
bool f=0;
for(auto&x:m){
if(f)os<<", ";
f=1;
os<<x;
}
return os<<"}";
}
template<class T>
ostream& operator<<(ostream&os,queue<T>q){
vc<T>a;
while(q.size())a.pb(q.front()),q.pop();
return os<<a;
}
template<class T>
ostream& operator<<(ostream&os,stack<T>s){
vc<T>a;
while(s.size())a.pb(s.top()),s.pop();
return os<<a;
}
template<class T,class C,class F>
ostream& operator<<(ostream&os,priority_queue<T,C,F>q){
vc<T>a;
while(q.size())a.pb(q.top()),q.pop();
return os<<a;
}
void debug_out(){cout<<endl;}
template<class T,class... Ts>
void debug_out(const T&x,const Ts&...xs){
cout<<x;
if constexpr(sizeof...(xs))cout<<" ",debug_out(xs...);
else cout<<endl;
}
#define dbg(...) cout<<"["<<#__VA_ARGS__<<"] = ",debug_out(__VA_ARGS__)
#endif
struct TemplateSetup{
TemplateSetup(){
#ifdef LOCAL
freopen("input.txt","r",stdin);
freopen("output.txt","w",stdout);
#endif
cin.tie(0)->sync_with_stdio(0);
#ifdef LOCAL
cout<<fixed<<setprecision(6);
dbg("==============="s);
#else
cout<<fixed<<setprecision(20);
#endif
}
};
inline TemplateSetup template_setup;
#endif
#line 2 "lib/graph/base.hpp"
#include<type_traits>
struct Unweighted{
Unweighted()=default;
Unweighted(int){}
operator int()const{return 1;}
};
template<class T=Unweighted>
struct Edge{
int from,to,id;
[[no_unique_address]] T cost;
#ifdef LOCAL
friend ostream&operator<<(ostream&os,const Edge&e){
return os<<"{from:"<<e.from<<",to:"<<e.to<<",id:"<<e.id<<",cost:"<<e.cost<<"}";
}
#endif
};
template<class T,class=void>struct IsEdge:false_type{};
template<class T>struct IsEdge<T,void_t<decltype(declval<T>().from),decltype(declval<T>().to),decltype(declval<T>().id),decltype(declval<T>().cost)>>:true_type{};
struct EmptyStorage{};
template<bool is_directed,class T=Unweighted>
struct StaticGraph{
constexpr static bool directed(){return is_directed;}
using Edge=conditional_t<IsEdge<T>::value,T,::Edge<T>>;
using cost_t=decltype(declval<Edge>().cost);
private:
int n,m,added=0;
mutable bool csr_built=false;
[[no_unique_address]] mutable conditional_t<is_directed,bool,EmptyStorage> inv_built{};
vc<Edge>_all_edges;
mutable vc<int>csr_start;
mutable vc<Edge>csr_edge;
[[no_unique_address]] mutable conditional_t<is_directed,vc<int>,EmptyStorage>inv_start;
[[no_unique_address]] mutable conditional_t<is_directed,vc<Edge>,EmptyStorage>inv_edge;
public:
StaticGraph(int n):n(n),m(-1){assert(n>=0);csr_start.resize(n+1);}
StaticGraph(int n,int m):n(n),m(m){assert(n>=0&&m>=0);csr_start.resize(n+1);_all_edges.reserve(m);}
void resize(int size){
assert(n<=size);
assert(!csr_built);
n=size;
csr_start.resize(n+1);
}
void add_edge(const Edge&e){
assert(0<=e.from&&e.from<n&&0<=e.to&&e.to<n);
assert(m==-1||added<m);
_all_edges.push_back(e);
csr_built=false;
if constexpr(is_directed)inv_built=false;
if(++added==m)build();
}
void add_edge(int a,int b,cost_t cost=1,int id=-1){
assert(0<=a&&a<n&&0<=b&&b<n);
assert(m==-1||added<m);
if(id==-1)id=(int)_all_edges.size();
_all_edges.push_back({a,b,id,cost});
csr_built=false;
if constexpr(is_directed)inv_built=false;
if(++added==m)build();
}
template<int substract=0>
void input(int edge_count){
assert(edge_count>=0);
rep(i,edge_count){
INT(a,b);
a-=substract;
b-=substract;
add_edge(a,b);
}
}
void build()const{
if(csr_built)return;
csr_built=true;
csr_start.assign(n+1,0);
for(auto&e:_all_edges){
csr_start[e.from]++;
if constexpr(!is_directed)csr_start[e.to]++;
}
rep(i,n)csr_start[i+1]+=csr_start[i];
csr_edge.resize(csr_start[n]);
for(auto it=_all_edges.rbegin();it!=_all_edges.rend();++it){
auto&e=*it;
csr_edge[--csr_start[e.from]]=e;
if constexpr(!is_directed)csr_edge[--csr_start[e.to]]={e.to,e.from,e.id,e.cost};
}
}
void build_inv()const{
if constexpr(!is_directed){
build();
return;
}else{
if(inv_built)return;
inv_built=true;
inv_start.assign(n+1,0);
for(auto&e:_all_edges){
inv_start[e.to]++;
}
rep(i,n)inv_start[i+1]+=inv_start[i];
inv_edge.resize(inv_start[n]);
for(auto it=_all_edges.rbegin();it!=_all_edges.rend();++it){
auto&e=*it;
inv_edge[--inv_start[e.to]]={e.to,e.from,e.id,e.cost};
}
}
}
const vc<Edge>&all_edges()const{return _all_edges;}
int edge_size()const{return (int)_all_edges.size();}
Edge get_edge(int id)const{
assert(0<=id&&id<edge_size());
return _all_edges[id];
}
int out_deg(int u)const{assert(0<=u&&u<n);build();return csr_start[u+1]-csr_start[u];}
int in_deg(int u)const{
assert(0<=u&&u<n);
if constexpr(!is_directed){
return out_deg(u);
}else{
build_inv();
return inv_start[u+1]-inv_start[u];
}
}
int deg(int u)const{return out_deg(u);}
template<class E>
struct Span{
E*l; E* r;
E*begin()const{return l;}
E*end()const{return r;}
int size()const{return r-l;}
E&back()const{return r[-1];}
E&operator[](int i){return l[i];}
const E&operator[](int i)const{return l[i];}
};
auto operator[](int u){
assert(0<=u&&u<n);build();
return Span<Edge>{csr_edge.data()+csr_start[u],csr_edge.data()+csr_start[u+1]};
}
auto operator[](int u)const{
assert(0<=u&&u<n);build();
return Span<const Edge>{csr_edge.data()+csr_start[u],csr_edge.data()+csr_start[u+1]};
}
auto inv(int u){
assert(0<=u&&u<n);
if constexpr(!is_directed){
return (*this)[u];
}else{
build_inv();
return Span<Edge>{inv_edge.data()+inv_start[u],inv_edge.data()+inv_start[u+1]};
}
}
auto inv(int u)const{
assert(0<=u&&u<n);
if constexpr(!is_directed){
return (*this)[u];
}else{
build_inv();
return Span<const Edge>{inv_edge.data()+inv_start[u],inv_edge.data()+inv_start[u+1]};
}
}
int size()const{return n;}
template<class F>vvc<F>adj()const{
vvc<F>res(n,vc<F>(n));
for(auto&e:all_edges()){
res[e.from][e.to]=e.cost;
if(directed()==false)res[e.to][e.from]=e.cost;
}
return res;
}
void clear(){
added=0;
csr_built=false;
if constexpr(is_directed)inv_built=false;
_all_edges.clear();_all_edges.shrink_to_fit();
csr_start.assign(n+1,0);csr_start.shrink_to_fit();
csr_edge.clear();csr_edge.shrink_to_fit();
if constexpr(is_directed){
inv_start.clear();inv_start.shrink_to_fit();
inv_edge.clear();inv_edge.shrink_to_fit();
}
}
template<class F>
void sort(int i,F f){
assert(0<=i&&i<n);
build();
sort(csr_edge.begin()+csr_start[i],csr_edge.begin()+csr_start[i+1],f);
}
template<class F>
void sort_inv(int i,F f){
assert(0<=i&&i<n);
if constexpr(!is_directed){
build();
sort(csr_edge.begin()+csr_start[i],csr_edge.begin()+csr_start[i+1],f);
return;
}
build_inv();
sort(inv_edge.begin()+inv_start[i],inv_edge.begin()+inv_start[i+1],f);
}
template<class F>
StaticGraph<is_directed,T>extract(F f)const{
StaticGraph<is_directed,T>res(n);
for(auto&e:_all_edges)if(f(e))res.add_edge(e);
return res;
}
template<class F>
StaticGraph<1,T>reorder(F f)const{
StaticGraph<1,T>res(n);
for(auto&e:_all_edges){
if(f(e))res.add_edge(e);
else res.add_edge({e.to,e.from,e.id,e.cost});
}
return res;
}
};
#line 3 "lib/tree/base.hpp"
template<class T=Unweighted>
struct Tree{
using Graph=StaticGraph<0,T>;
using Edge=typename Graph::Edge;
using cost_t=typename Graph::cost_t;
mutable Graph g;
mutable int built_hld=-1;
int n;
mutable vc<int>in,out,head,size_,par,depth,ord;
Tree(int n):n(n),g(n,n-1){}
void add_edge(const Edge&e){
g.add_edge(e);
}
void add_edge(int a,int b,cost_t cost=1,int id=-1){
g.add_edge(a,b,cost,id);
}
bool is_to_par(auto&e)const{
return par[e.from]==e.to;
}
int size()const{
return n;
}
auto operator[](int u)const{
assert(0<=u&&u<n);
return g[u];
}
auto operator[](int u){
assert(0<=u&&u<n);
return g[u];
}
template<int substract>
void input(){
rep(i,n-1){
INT(a,b);
a-=substract;
b-=substract;
g.add_edge(a,b);
}
}
template<int disjoint=0>
void build(int root=0)const{
assert(0<=root&&root<n);
if(built_hld!=-1){
return;
}
built_hld=disjoint;
in.resize(n);
out.resize(n);
head.resize(n);
size_.assign(n,1);
par.resize(n);
depth.resize(n);
ord.assign(n*(disjoint+1),-1);
par[root]=-1;
depth[root]=0;
head[root]=root;
int timer=0;
auto dfs=[&](auto&dfs,int u,int v,int d)->void{
depth[u]=d++;
auto s=g[u];
int heavy=-1,par_id=-1;
rep(i,s.size()){
auto&e=s[i];
if(e.to==v){
par_id=i;
continue;
}
par[e.to]=u;
dfs(dfs,e.to,u,d);
size_[u]+=size_[e.to];
if(heavy==-1||size_[s[heavy].to]<size_[e.to])heavy=i;
}
if(heavy!=-1&&heavy!=0){
swap(s[heavy],s[0]);
if(par_id==0)par_id=heavy;
else if(par_id==heavy)par_id=0;
}
if(par_id!=-1&&par_id+1!=s.size()){
swap(s[par_id],s[s.size()-1]);
}
};dfs(dfs,root,-1,0);
{auto dfs=[&](auto&dfs,int u)->void{
in[u]=timer;
ord[timer++]=u;
auto s=g[u];
bool first=true;
rep(i,s.size()){
auto&e=s[i];
if(e.to==par[u])continue;
head[e.to]=first?head[u]:e.to;
first=false;
dfs(dfs,e.to);
}
if constexpr(disjoint)out[u]=timer++;
else out[u]=timer;
};dfs(dfs,root);}
rep(u,n){
auto s=g[u];
int ce=s.size()-(par[u]!=-1);
if(ce>1)sort(s.begin()+1,s.begin()+ce,[&](const Edge&a,const Edge&b){return in[a.to]<in[b.to];});
}
}
auto heavy_edge(int u)const{
assert(0<=u&&u<n);
build();
auto s=g[u];
int sz=s.size(),ce=(par[u]==-1?sz:sz-1);
if(ce<=0)return typename Graph::template Span<const Edge>{s.l,s.l};
return typename Graph::template Span<const Edge>{s.l,s.l+1};
}
auto light_edges(int u)const{
assert(0<=u&&u<n);
build();
auto s=g[u];
int sz=s.size(),ce=(par[u]==-1?sz:sz-1);
if(ce<=1)return typename Graph::template Span<const Edge>{s.l,s.l};
return typename Graph::template Span<const Edge>{s.l+1,s.l+ce};
}
int lca(int a,int b)const{
assert(0<=a&&a<n&&0<=b&&b<n);
build();
auto&h=head;
auto&d=depth;
auto&p=par;
while(1){
if(h[a]==h[b]){
if(d[a]<d[b])return a;
return b;
}
if(d[h[a]]<d[h[b]])swap(a,b);
a=p[h[a]];
}
}
int dist(int a,int b)const{
assert(0<=a&&a<n&&0<=b&&b<n);
build();
return depth[a]+depth[b]-2*depth[lca(a,b)];
}
int jumpup(int a,int k)const{
assert(0<=a&&a<n);
build();
if(k<0||depth[a]<k)return -1;
auto&I=in;
auto&H=head;
auto&P=par;
auto&O=ord;
while(k>0){
int x=I[a]-I[H[a]];
if(x>=k){
return O[I[a]-k];
}
k-=x+1;
a=P[H[a]];
}
return a;
}
int jump(int s,int t,int k)const{
assert(0<=s&&s<n&&0<=t&&t<n);
build();
int L=lca(s,t);
int D=depth[s]+depth[t]-2*depth[L];
if(depth[s]-depth[L]>=k){
return jumpup(s,k);
}else{
return jumpup(t,D-k);
}
}
int to(int x,int y)const{
assert(0<=x&&x<n&&0<=y&&y<n&&x!=y);
build();
if(in[y]<in[x]||out[x]<=in[y])return g[x].size()-1;
auto s=g[x];
int ce=s.size()-(par[x]!=-1);
if(in[s[0].to]<=in[y]&&in[y]<out[s[0].to])return 0;
int l=1,r=ce;
while(l<r){
int m=(l+r)/2;
if(in[s[m].to]<=in[y])l=m+1;
else r=m;
}
return l-1;
}
vc<pair<int,int>>Query(int s,int t,bool edge=false)const{
assert(0<=s&&s<n&&0<=t&&t<n);
build();
auto&h=head;
auto&d=depth;
auto&I=in;
auto&P=par;
vc<pair<int,int>>rs,rt;
while(h[s]!=h[t]){
if(d[h[s]]>d[h[t]]){
rs.push_back({I[s],I[h[s]]});
s=P[h[s]];
}else{
rt.push_back({I[h[t]],I[t]});
t=P[h[t]];
}
}
if(s!=t||!edge){
if(d[s]>d[t]){
rs.push_back({I[s],I[t]+edge});
}else{
rt.push_back({I[s]+edge,I[t]});
}
}
rs.reserve(rs.size()+rt.size());
for(auto it=rt.rbegin();it!=rt.rend();++it)rs.push_back(*it);
return rs;
}
pair<int,int>get_diameter()const{
assert(n>0);
auto find_farthest=[&](int from)->int{
vc<int>d(n),p(n,-2),st(1,from);
p[from]=-1;
int far=from;
while(!st.empty()){
int u=st.back();
st.pop_back();
if(d[far]<d[u])far=u;
for(auto&e:g[u])if(e.to!=p[u]){
p[e.to]=u;
d[e.to]=d[u]+1;
st.push_back(e.to);
}
}
return far;
};
int v1=find_farthest(0);
int v2=find_farthest(v1);
return {v1,v2};
}
};
#line 3 "a.cpp"
void solve(){
INT(n);
Tree base(n);
base.input<1>();
vc<int>dp0(n),dp1(n);
auto dfs=[&](auto&dfs,int u,int v)->void{
int max_delta=-1e9;
ll S=0;
ll S3=0;
for(auto&e:base[u]){
if(e.to==v)continue;
dfs(dfs,e.to,u);
chmax(max_delta,dp0[e.to]-dp1[e.to]);
S+=dp1[e.to];
S3+=max(dp0[e.to],dp1[e.to]);
}
dp0[u]=S3;
dp1[u]=max(0ll,max_delta+S+1);
};
dfs(dfs,0,-1);
dbg(dp0);
dbg(dp1);
PRT(max(dp0[0],dp1[0]));
}
signed main(){
int t=1;
// cin >> t;
while(t--)solve();
}