Submission #1094680

#	Time	Username	Problem	Language	Result	Execution time	Memory
1094680		huyngo	The Big Prize (IOI17_prize)	C++17	20 / 100	3 ms	5204 KiB

prize

#include "prize.h"
#include<bits/stdc++.h>
using namespace std;


int find_best(int n) {
	vector<vector<int>> info(n);
	map<int, int> found;
	auto get = [&](int i) -> vector<int> {
		if (info[i].size())
			return info[i];
		info[i] = ask(i);
		found[info[i][0] + info[i][1]]++;
		// for (int i = 0; i < n; ++i)
		// 	cerr << info[i].size() << ' ';
		// cerr << '\n';
		return info[i];
		};

	auto findNext = [&](int l, int r, int cur) -> int {
		int lo = l, hi = r, x = -1;
		while (lo <= hi) {
			int md = (lo + hi) / 2;
			if (get(md)[0] + get(md)[1] > cur) {
				if (get(md)[0] <= found[cur]) {
					x = md;
					lo = md + 1;
				}
				else {
					hi = md - 1;
				}
			}
			else if (get(md)[0] + get(md)[1] < cur) {
				if (get(md)[0] == 0)
					return md;
				else
					hi = md - 1;
			}
			else {
				if (get(md)[0] == 0) {
					found[cur] += get(md)[1] - get(l - 1)[1] - 1;
					return md;
				}
				else {
					hi = md - 1;
				}
			}
		}
		return x;
		};

	found[0] = 0;
	int l = 0, r = n - 1;
	get(0);
	while (!found[0]) {
		l = findNext(l + 1, r, get(l)[0] + get(l)[1]);
		// cerr << l << '\n';
		if (l == -1) break;
	}
	for (int i = 0; i < n; ++i) {
		if (info[i].size() && info[i][0] + info[i][1] == 0)
			return i;
	}
	return 0;
}

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