제출 #1111946

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1111946		epicci23	통행료 (IOI18_highway)	C++17	12 / 100	113 ms	72008 KiB

highway

#include "bits/stdc++.h"
#include "highway.h"
#define ll long long
#define all(v) v.begin() , v.end()
#define sz(a) (ll)a.size()
using namespace std;

const ll N = 2e5 + 5;

vector<ll> v[N],Xor,depth[N];
vector<int> Res;
ll n,m,A,B,Dist,vis[N],par[N],sub[N];

inline ll oth(ll c,ll u) {return Xor[c] ^ u;}

void upd(ll c,ll d){
  sub[c]=1;
  depth[d].push_back(c);
  for(ll ind:v[c]){
    ll x = oth(ind,c);
  	if(ind==par[c] || vis[x]) continue;
  	par[x]=ind;
    upd(x,d+1);
    sub[c]+=sub[x];
  }
}

ll we_know_root(ll rt){
  for(ll i=0;i<N;i++) depth[i].clear();
  par[rt]=-1;
  upd(rt,0);
  ll l = 0 , r = sz(depth[Dist]) - 1;
  
  while(l<r){
  	ll mid = (l+r)/2;
    Res.assign(m,0);
    for(ll i=0;i<=mid;i++){
      ll cur = depth[Dist][i];
      while(cur != rt){
        Res[par[cur]]=1;
        cur = oth(par[cur], cur);
      }
    }
    if(ask(Res)==Dist*B) r=mid;
    else l=mid+1;
  }

  return depth[Dist][l];
}

void find_pair(int _n, vector<int> U, vector<int> V, int _A, int _B){
  A=_A,B=_B;
  m = sz(U),n = _n;
  for(ll i=0;i<m;i++){
  	Xor.push_back(U[i]^V[i]);
    v[U[i]].push_back(i);
    v[V[i]].push_back(i);
  }
  Res.assign(m,0);
  Dist = ask(Res) / A;
  answer(0, (int) we_know_root(0));
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 0 / 6
• Subtask 4: 0 / 33
• Subtask 5: 0 / 18
• Subtask 6: 0 / 31