Submission #1168369

#	Time	Username	Problem	Language	Result	Execution time	Memory
1168369		Faisal_Saqib	Triumphal arch (POI13_luk)	C++20	100 / 100	358 ms	27672 KiB

luk

/*
    VENI VIDI VICI
*/

// #pragma GCC optimize("Ofast","unroll-all-loops","fast-math","no-stack-protector","give-no-fuck")
#include <bits/stdc++.h>
// #include <iostream>
// #include <vector>
// #include <algorithm>
// #include <set>
// #include <map>

using namespace std;
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()

#define rep(i,x, n) for (int i = (x); i < (n); ++i)
#define repr(i,x, n) for (int i = (n) - 1; i >= (x); --i)
// #define sum accumulate

using i128 = __int128;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using str = string;
using pi = pair<int, int>;
using pl = pair<ll, ll>;


using vi = vector<int>;
using vl = vector<ll>;
using vpi = vector<pair<int, int>>;
using vvi = vector<vi>;

template<class T>
istream& operator>>(istream& is, vector<T>& v) {
    for(auto &i:v) is>>i;
    return is;
}
template<class T1,class T2>
istream& operator>>(istream& is, pair<T1,T2>& p) {
    is>>p.fi>>p.se;
    return is;
}
template<class T>
ostream& operator<<(ostream& os, const vector<T>& v) {
    for(const auto &i:v) os<<i<<' ';
    return os;
}
template<class T1,class T2>
ostream& operator<<(ostream& os, const pair<T1,T2>& p) {
    os<<p.fi<<' '<<p.se; return os;
}
void pyn(bool x)
{
    cout<<(x?"YES":"NO")<<endl;
}
void pYN(bool x)
{
    cout<<(x?"Yes":"No")<<endl;
}
void pAB(bool x)
{
    cout<<(x?"Alice":"Bob")<<endl;
}
ll powmod(ll a,ll b,ll modulo)
{
  if(b==0){
    return 1;
  }
  ll temp=powmod(a,b/2,modulo);
  if(b%2==0){
    return (temp*temp)%modulo;
  }
  else{
    return (a*((temp*temp)%modulo))%modulo;
  }
}
bool Prime(ll n){
    for (ll i = 2; i*i <= n; i++)
        if (n % i == 0)
            return false;
    return (n>1);
}

const ll N=3e5+100;
vl ma[N];
ll dp[N];
void dfs(int x,int p=-1,int vl=1)
{
    dp[x]=vl-ma[x].size()+(p!=-1);
    for(auto y:ma[x])
    {
        if(y==p)continue;
        dfs(y,x,vl);
        dp[x]+=min(dp[y],0ll);
    }
}
bool check(ll x)
{
    dfs(1,-1,x);
    return dp[1]>=0;
}
void solve()
{
    ll n;
    cin>>n;
    rep(i,1,n)
    {
        int x,y;
        cin>>x>>y;
        ma[x].pb(y);
        ma[y].pb(x);
    }
    ll l=-1,r=n;
    // zero can be answer
    while(l+1<r)
    {
        ll mid=(l+r)/2;
        if(check(mid))
        {
            r=mid;
        }
        else
        {
            l=mid;
        }
    }
    cout<<r<<endl;
}

int main() {
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int uwu=1;
    // cin>>uwu;

    while(uwu--) {
        solve();
    }
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10