Submission #587707

#	Time	Username	Problem	Language	Result	Execution time	Memory
587707		Koosha_mv	Highway Tolls (IOI18_highway)	C++14	51 / 100	236 ms	262144 KiB

highway

#include "highway.h"
#include <bits/stdc++.h>
using namespace std;
#define dbgv(v) cout<<#v<<" = "; f(i,0,v.size()) cout<<v[i]<<" "; cout<<endl
#define dbga(a,x,y) cout<<#a<<" = "; f(i,x,y) cout<<a[i]<<" "; cout<<endl
#define erorp(x) cout<<#x<<"={"<<x.F<<" , "<<x.S<<"}"<<endl
#define eror(x) cout<<#x<<'='<<(x)<<endl
#define f_(i,a,b) for(int i=a;i>=b;i--)
#define f(i,a,b) for(int i=a;i<b;i++)
#define nb(x) __builtin_popcount(x)
#define all(v) v.begin(),v.end()
#define bit(n,k) (((n)>>(k))&1)
#define Add(x,y) x=(x+y)%mod
#define maxm(a,b) a=max(a,b)
#define minm(a,b) a=min(a,b)
#define lst(x) x[x.size()-1]
#define sz(x) int(x.size())
#define mp make_pair
#define ll long long
#define pb push_back
#define S second
#define F first

const int N=2e5+99;

int n,m,A,B,S,T,par[N],f[N];
ll ST;
vector<int> w,vec;
vector<pair<int,int>> g[N];

void reset(int x){
  fill(w.begin(),w.end(),x);
}
void dfs(int u){
  for(auto [v,id] : g[u]){
    if(v==par[u]) continue ;
    f[v]=id;
    par[v]=u;
    dfs(v);
  }
  vec.pb(u);
}
int find(int rt){
  fill(par,par+N,-1);
  vec.clear();
  dfs(rt);
  int l=0,r=n;
  while(l+1<r){
    int mid=(l+r)>>1;
    reset(1);
    f(i,0,mid) w[f[vec[i]]]=0;
    ll res=ask(w);
    if(res<ST*B){
      r=mid;
    }
    else{
      l=mid;
    }
  }
  f(i,1,n+1) reverse(all(g[i]));
  return vec[l];
}

void find_pair(int _n,vector<int> U,vector<int> V,int _A,int _B){
  n=_n,m=U.size(),A=_A,B=_B;
  f(i,0,m){
    g[U[i]].pb({V[i],i});
    g[V[i]].pb({U[i],i});
  }
  w.resize(m);
  ST=ask(w)/A;
  S=find(0);
  T=find(S);
  if(S==T){
    while(ST--){
      T=par[T];
    }
  }
  answer(S,T);
}
/*
3 2 1 2 0 2
0 1
1 2
*/

Compilation message (stderr)

highway.cpp: In function 'void dfs(int)':
highway.cpp:35:12: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   35 |   for(auto [v,id] : g[u]){
      |            ^

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