Submission #1025426

#	Time	Username	Problem	Language	Result	Execution time	Memory
1025426		huutuan	커다란 상품 (IOI17_prize)	C++14	90 / 100	152 ms	15300 KiB

prize

#include "prize.h"

#include <bits/stdc++.h>

using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;

template<class T>
using ordered_set=tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

vector<int> mem[200000];

vector<int> Ask(int i){
   if (mem[i].size()) return mem[i];
   return mem[i]=ask(i);
}

int find_best(int n) {
   for (int i=0; i<n; ++i) mem[i].clear();
   // if (n<=5000){
   //    for (int i=0; i<n; ++i){
   //       auto tmp=ask(i);
   //       if (tmp[0]+tmp[1]==0) return i;
   //    }
   //    return -1;
   // }
   int m=n;
   int mx=0;
   while (m>1){
      m=(int)sqrt(m);
      mx+=m;
   }
   vector<pair<int, int>> v(mx);
   for (int i=0; i<mx; ++i){
      auto tmp=Ask(i);
      v[i]={tmp[0], tmp[1]};
      if (tmp[0]+tmp[1]==0) return i;
   }
   int cnt=0;
   for (auto &i:v) cnt=max(cnt, i.first+i.second);
   ordered_set<int> st, id;
   for (int i=0; i<mx; ++i) if (v[i].first+v[i].second!=cnt) id.insert(i);
   for (int i=mx; i<n; ++i) st.insert(i);
   int rem=cnt-(int)id.size();
   while (rem){
      int l=0, r=(int)st.size()-1;
      while (l<=r){
         int mid=(l+r)>>1;
         int i=*st.find_by_order(mid);
         auto tmp=Ask(i);
         if (tmp[0]+tmp[1]!=cnt){
            id.insert(i);
            st.erase(i);
            --rem;
            break;
         }
         int cntl=tmp[0];
         cntl-=id.order_of_key(i);
         if (cntl) r=mid;
         else l=mid+1;
      }
   }
   for (int i:id){
      auto tmp=Ask(i);
      if (tmp[0]+tmp[1]==0) return i;
   }
   return -1;
}

• Subtask 1: 20 / 20
• Subtask 2: 70 / 80