Submission #989518

#	Time	Username	Problem	Language	Result	Execution time	Memory
989518		AdamGS	Roller Coaster Railroad (IOI16_railroad)	C++17	100 / 100	505 ms	49024 KiB

railroad

#include "railroad.h"
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const int LIM=4e5+7, INF=1e9+7;
vector<int>skal;
map<int,int>mp;
ll jaki[LIM];
int F[LIM], akt;
int fnd(int x) {
  if(F[x]==x) return x;
  return F[x]=fnd(F[x]);
}
bool uni(int a, int b) {
  if(fnd(a)==fnd(b)) return false;
  F[fnd(b)]=fnd(a);
  return true;
}
ll plan_roller_coaster(vector<int>s, vector<int>t) {
  s.pb(INF);
  t.pb(0);
  int n=s.size();
  for(auto i : s) skal.pb(i);
  for(auto i : t) skal.pb(i);
  sort(all(skal));
  for(auto i : skal) if(mp.find(i)==mp.end()) {
    jaki[akt]=i;
    mp[i]=akt++;
  }
  rep(i, akt) F[i]=i;
  vector<pair<int,int>>P;
  rep(i, n) {
    P.pb({s[i], -1});
    P.pb({t[i], 1});
  }
  sort(all(P));
  ll lst=P[0].st, sum=0, ans=0;
  for(auto i : P) {
    if(i.st!=lst) {
      if(sum<0) ans-=sum*(i.st-lst);
      if(sum!=0) uni(mp[i.st], mp[lst]);
    }
    sum+=i.nd;
    lst=i.st;
  }
  rep(i, n) uni(mp[s[i]], mp[t[i]]);
  vector<pair<ll,pair<int,int>>>kraw;
  rep(i, akt-1) kraw.pb({jaki[i+1]-jaki[i], {i, i+1}});
  sort(all(kraw));
  for(auto i : kraw) if(uni(i.nd.st, i.nd.nd)) ans+=i.st;
  return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 23 / 23
• Subtask 3: 30 / 30
• Subtask 4: 36 / 36