Submission #589023

#	Time	Username	Problem	Language	Result	Execution time	Memory
589023		Koosha_mv	Highway Tolls (IOI18_highway)	C++14	72 / 100	290 ms	15016 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,cnt,S,T,par[N],mark[N],f[N];
ll A,B,ST;
vector<int> w,vec,U,V;
vector<pair<int,int>> g[N];

ll Ask(vector<int> w){
  cnt++;
  if(cnt>52) assert(0);
  return ask(w);
}
void reset(int x){
  fill(all(w),x);
}
int Root(){
  int l=0,r=n;
  while(l+1<r){
    int mid=(l+r)>>1;
    reset(0);
    f(i,0,mid) w[i]=1;
    if(ST*A<Ask(w)){
      r=mid;
    }
    else{
      l=mid;
    }
  }
  return U[l];
}
int find(int x){
  fill(mark,mark+N,0);
  vector<int> vec;
  vec.pb(x);
  mark[x]=1;
  f(i,0,int(vec.size())){
    int u=vec[i];
    for(auto [v,id] : g[u]){
      if(mark[v]==0){
        vec.pb(v);
        f[v]=id;
        mark[v]=1;
      }
    }
  }
  if(vec.size()!=n) assert(0);
  int l=1,r=n;
  while(l+1<r){
    int mid=(l+r)>>1;
    reset(1);
    f(i,1,mid){
      w[f[vec[i]]]=0;
    }
    if(Ask(w)==A*ST){
      r=mid;
    }
    else{
      l=mid;
    }
  }
  return vec[l];
}

void find_pair(int _n,vector<int> _U,vector<int> _V,int _A,int _B){
  U=_U,V=_V;
  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;
  int rt=Root();
  S=find(rt);
  T=find(S);
  answer(S,T);
}
/*
3 2 1 2 1 2
0 1
1 2
*/

Compilation message (stderr)

highway.cpp: In function 'int find(int)':
highway.cpp:61:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   61 |     for(auto [v,id] : g[u]){
      |              ^
highway.cpp:69:16: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   69 |   if(vec.size()!=n) assert(0);
      |      ~~~~~~~~~~^~~

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 6 / 6
• Subtask 4: 33 / 33
• Subtask 5: 0 / 18
• Subtask 6: 21 / 31