Submission #937879

#	Time	Username	Problem	Language	Result	Execution time	Memory
937879		Macker	The Big Prize (IOI17_prize)	C++17	90 / 100	63 ms	6456 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>

typedef long long ll;
#define all(v) v.begin(), v.end()
#define FOR(i, n) for (int i = 0; i < n; i++)

using namespace std;

int find_best(int n) {
	int mn = 0;
	FOR(i, min(530, n)){
		auto res = ask(i);
		mn = max(mn, res[0] + res[1]);
	}
	vector<int> pos;
	vector<vector<int>> val(n);
	int l = 0, r = 1;
	FOR(i, mn){
		while(r < n - 1){
			auto ret = ask(r);
			if(ret[0] + ret[1] != mn) break;
			if(ret[0] > i) break;
			r += (r - l); 
			if(r >= n){
				r = n - 1;
				break;
			}
		}
		while(l < r){
			int mid = (l + r) / 2;
			vector<int> ret;
			if(val[mid].size()) ret = val[mid];
			else ret = val[mid] = ask(mid);

			if(ret[0] + ret[1] == 0) return mid;

			if(ret[0] + ret[1] != mn) r = mid;
			else if(ret[0] > i) r = mid - 1;
			else l = mid + 1;
		}
		pos.push_back(r);
		if(r != n - 1) {l++; r += 2;}
	}
	for (auto i : pos) {
		vector<int> ret;
		if(val[i].size()) ret = val[i];
		else ret = val[i] = ask(i);
		if(ret[0] + ret[1] == 0) return i;
	}
	return 0;
}

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