Submission #1113328

#	Time	Username	Problem	Language	Result	Execution time	Memory
1113328		epicci23	The Big Prize (IOI17_prize)	C++17	20 / 100	196 ms	1452 KiB

prize

#include "bits/stdc++.h"
#include "prize.h"
//#define int long long
#define all(v) v.begin() , v.end()
#define sz(a) (int)a.size()
using namespace std;

const int S = 100;
const int S2 = 20;

int L = -1;
vector<int> Cache;
map<int,vector<int>> dp;

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

int ask_all(int l,int r){
  for(int i=l;i<=r;i++){
    vector<int> x = Ask(i);
    if(x[0]+x[1]==0) return i;
    if(x[0]+x[1]==Cache[0]+Cache[1]) Cache=x;
  }
  return -23;
}

int find_best(int n){
  if(n<=1000) return ask_all(0,n-1);
  
  for(int i=0;i<500;i++){
    vector<int> x = Ask(i);
    if(x[0]+x[1]==0) return i;
    if(L==-1){
      L=i;
      Cache=x;
    }
    else if(x[0]+x[1]>Cache[0]+Cache[1]){
      L=i;
      Cache=x;
    }
    else if(x[0]+x[1]==Cache[0]+Cache[1]){
      L=i;
      Cache=x;
    }
  }
  
  while(L+S<n){
    vector<int> x = Ask(L+S);
    if(x[0]+x[1]==0) return L+S;
    if(x[0]+x[1]==Cache[0]+Cache[1] && Cache[1]==x[1]){
      L+=S;
      Cache=x;
      continue;
    }
    int p = L;
    while(p+S2<L+S){
      p+=S2;
      vector<int> u = Ask(p);
      if(u[0]+u[1]==0) return p;
      if(u[0]+u[1]==Cache[0]+Cache[1] && Cache[1]==u[1]) Cache=u;
      else{
        int xd = ask_all(p-S2+1,p-1);
        if(xd!=-23) return xd;
      }
      if(u[0]+u[1]==Cache[0]+Cache[1]) Cache=u;
    }
    int xd = ask_all(p+1,L+S-1);
    if(xd!=-23) return xd;
    L+=S;
    if(x[0]+x[1]==Cache[0]+Cache[1]) Cache=x;
  }
  return ask_all(L+1,n-1);
}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 80