제출 #1063434

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1063434		fv3	The Big Prize (IOI17_prize)	C++14	0 / 100	61 ms	4440 KiB

prize

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

using namespace std;

int N;

vector<int> st;
int nt = 1;

int get_offset(int i, int k, int x, int y)
{
	if (x > i) return 0;
	if (y <= i) return st[k];
	int c = (x + y) / 2;
	return get_offset(i, k*2, x, c) + get_offset(i, k*2|1, c+1, y);
}
void add(int index)
{
	st[nt + index] = 1;
	for (int i = (nt + index) / 2; i >= 1; i /= 2)
		st[i] = st[i*2] + st[i*2|1];
}

int prize_pos = 0;
bool attempt(int &mx_cnt)
{
	st = vector<int>(2 * nt);

	cerr << "mx_cnt = " << mx_cnt << '\n';

	for (int q = 0; 1; q++)
	{
		int l = 0, r = N - 1;

		while (l < r)
		{
			int c = (l + r) / 2;
			int index = c + get_offset(c, 1, 0, nt - 1);

			auto val = ask(index);
			int cnt = val[0] + val[1];

			if (cnt == 0)
			{
				prize_pos = index;
				return true;
			}
			if (cnt < mx_cnt)
			{
				add(index);
				r--;
				continue;
			}
			if (cnt > mx_cnt)
			{
				mx_cnt = cnt;
				return false;
			}

			if (val[0] <= q)
				l = c + 1;
			else
				r = c - 1;
		}

		int index = l + get_offset(l, 1, 0, nt - 1);
		auto val = ask(index);
		int cnt = val[0] + val[1];
		if (cnt == 0)
		{
			prize_pos = index;
			return true;
		}
		add(index);
	}

	return true;
}

int find_best(int n)
{
	N = n;
	while (nt < N) nt <<= 1;
	st = vector<int>(2 * nt);

	int mx_cnt = 2;
	while (!attempt(mx_cnt));
	return prize_pos;
}

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