제출 #799664

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
799664		kirakaminski968	Roller Coaster Railroad (IOI16_railroad)	C++17	0 / 100	272 ms	524288 KiB

railroad

#include "railroad.h" 
#include <bits/stdc++.h>
#define ll long long 
using namespace std; 
struct dsu{
  int par[400005]; 
  void init(int N){
    for(int i = 0;i<=N;++i) par[i] = i; 
  }
  int finden(int x){
    return par[x] = (par[x] == x ? x : finden(x)); 
  }
  bool unite(int x, int y){
    x = finden(x); y = finden(y); 
    if(x == y){
      return false; 
    }
    par[y] = x; 
    return true; 
  }
}D; 
struct edge{
  int start, ende, wert; 
  bool operator<(const edge &e)const{
    return wert < e.wert;
  }
}; 
int cnt[400005]; 
ll plan_roller_coaster(vector<int> s, vector<int> t){
  vector<int> merged; int n = (int)s.size(); 
  for(int i = 0;i<n;++i) {merged.push_back(s[i]); merged.push_back(t[i]);}
  sort(merged.begin(),merged.end()); 
  merged.resize(unique(merged.begin(),merged.end())-merged.begin()); 
  D.init(merged.size()); 
  for(int i = 0;i<n;++i){
    s[i] = lower_bound(merged.begin(),merged.end(),s[i])-merged.begin(); 
    t[i] = lower_bound(merged.begin(),merged.end(),t[i])-merged.begin(); 
    cnt[s[i]]++; cnt[t[i]]--; D.unite(s[i],t[i]); 
  }
  int cur = 1; ll ans = 0;
  vector<edge> kanten; 
  for(int i = merged.size()-1;i>=0;--i){
    cur += cnt[i]; 
    if(cur < 0){
      ans += -1ll * cur * (merged[i]-merged[i-1]); 
      cnt[i-1] += cur; 
      D.unite(i-1,i); 
      cur = 0; 
    }
    if(cur > 0 && i > 0) D.unite(i,i-1); 
    else if(cur == 0) kanten.push_back({i-1,i,merged[i]-merged[i-1]}); 
  }
  sort(kanten.begin(),kanten.end()); 
  for(auto p : kanten){
    if(D.unite(p.start,p.ende)) ans += p.wert; 
  }
  return ans; 
}

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• Subtask 2: 0 / 23
• Subtask 3: 0 / 30
• Subtask 4: 0 / 36