Submission #1080308

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1080308	2024-08-29T08:45:35 Z	Elias	The Big Prize (IOI17_prize)	C++17	95.23 / 100	39 ms	4628 KB

prize

// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>

using namespace std;

#define ll long long

#ifdef _DEBUG

int find_best(int n);
std::vector<int> ask(int i);
#else
#include "prize.h"
#endif

int N;

vector<int> a, b;

int segSet(int l, int r, int i, int k, int x)
{
	if (l > k || r <= k)
		return b[i];
	if (l + 1 == r)
		return a[l] = b[i] = x;
	int m = (l + r) / 2;
	return b[i] = segSet(l, m, i * 2 + 1, k, x) + segSet(m, r, i * 2 + 2, k, x);
}

int segGet(int l, int r, int i, int ql, int qr)
{
	if (ql <= l && qr >= r)
		return b[i];
	if (ql >= r || qr <= l)
		return 0;
	int m = (l + r) / 2;
	return segGet(l, m, i * 2 + 1, ql, qr) + segGet(m, r, i * 2 + 2, ql, qr);
}

int asks = 0;

int getRecursive(int l, int r, int cnt_here, int cnt_l, int cnt_r)
{
	if (l >= r)
		return -1;

	if (cnt_here - segGet(0, N, 0, l, r) <= 0)
		return -1;

	int m = (l + r) / 2;
	int i = m;

	vector<int> answer;
	bool is_special = false;
	int diff_l = 0;
	int diff_r = 0;

	do
	{
		if (i == r)
			break;

		is_special = false;
		asks++;
		assert(asks < 10000);
		assert(i >= 0 && i < N);
		answer = ask(i);

		if (answer[0] + answer[1] == 0)
			return i;

		answer[0] -= cnt_l;
		answer[1] -= cnt_r;

		if (answer[0] + answer[1] != cnt_here)
		{
			is_special = true;
			i++;
		}
		else
		{
			answer[0] -= i - m;
			diff_l += i - m;
			diff_r += i - m;
		}
	} while (is_special);

	int left = -1;
	if (i == r)
		left = getRecursive(l, m, cnt_here - (i - m), cnt_l, cnt_r + (i - m));
	else
		left = getRecursive(l, m, answer[0], cnt_l, cnt_r + answer[1] + diff_r);

	if (left != -1)
		return left;

	return getRecursive(i + 1, r, answer[1], cnt_l + answer[0] + diff_l, cnt_r);
}

int find_best(int n)
{
	N = n;

	a.resize(n);
	b.resize(4 * n);

	vector<pair<int, int>> cnt_here;

	set<int> values;

	for (int k = 0; k < 750; k++)
	{
		int i = rand() % n;

		vector<int> answer = ask(i);

		if (answer[0] + answer[1] == 0)
			return i;

		values.insert(answer[0] + answer[1]);

		cnt_here.push_back({answer[0] + answer[1], i});

		if (values.size() >= 6)
			break;
	}

	sort(cnt_here.begin(), cnt_here.end());

	for (auto [x, i] : cnt_here) {
		if (x != cnt_here.back().first) {
			segSet(0, N, 0, i, 1);
		}
	}

	int result = getRecursive(0, n, cnt_here.back().first, 0, 0);

	assert(result != -1);

	vector<int> answer = ask(result);

	assert(answer[0] + answer[1] == 0);

	return result;
}

#ifdef _DEBUG

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

static const int max_q = 10000;
static int n;
static int query_count = 0;
static vector<int> g;
static vector<vector<int>> rank_count;

vector<int> ask(int i)
{
	query_count++;
	if (query_count > max_q)
	{
		cerr << "Query limit exceeded" << endl;
		exit(0);
	}

	if (i < 0 || i >= n)
	{
		cerr << "Bad index: " << i << endl;
		exit(0);
	}

	vector<int> res(2);
	res[0] = rank_count[g[i] - 1][i + 1];
	res[1] = rank_count[g[i] - 1][n] - res[0];
	return res;
}

int main()
{
	for (int t = 10; t <= 97; t++)
	{
		string path = "/home/elias/Downloads/ioi2017tests/prize/tests/2-" + to_string(t) + ".out";
		freopen(path.c_str(), "r", stdin);

		string blub;
		cin >> blub;

		cin >> n;
		cin >> blub >> blub;

		query_count = 0;
		g.clear();
		rank_count.clear();
		asks = 0;

		g.resize(n);
		for (int i = 0; i < n; i++)
		{
			cin >> g[i];
			if (g[i] < 1)
			{
				cerr << "Invalid rank " << g[i] << " at index " << i << endl;
				exit(0);
			}
		}

		int max_rank = *max_element(g.begin(), g.end());

		rank_count.resize(max_rank + 1, vector<int>(n + 1, 0));
		for (int r = 0; r <= max_rank; r++)
		{
			for (int i = 1; i <= n; i++)
			{
				rank_count[r][i] = rank_count[r][i - 1];
				if (g[i - 1] == r)
					rank_count[r][i]++;
			}
		}

		for (int i = 0; i <= n; i++)
			for (int r = 1; r <= max_rank; r++)
				rank_count[r][i] += rank_count[r - 1][i];

		int res = find_best(n);
		assert(g[res] == 1);
		cout << res << " " << g[res]  << endl
			 << "Query count: " << query_count << endl;
	}
	return 0;
}

#endif

Subtask #1

20.0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	4184 KB	Output is correct
2	Correct	5 ms	4184 KB	Output is correct
3	Correct	4 ms	4184 KB	Output is correct
4	Correct	5 ms	4184 KB	Output is correct
5	Correct	7 ms	4448 KB	Output is correct
6	Correct	4 ms	4184 KB	Output is correct
7	Correct	5 ms	4184 KB	Output is correct
8	Correct	5 ms	4380 KB	Output is correct
9	Correct	6 ms	4440 KB	Output is correct
10	Correct	6 ms	4184 KB	Output is correct

Subtask #2

75.23 / 80.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	4184 KB	Output is correct
2	Correct	8 ms	4448 KB	Output is correct
3	Correct	6 ms	4440 KB	Output is correct
4	Correct	5 ms	4184 KB	Output is correct
5	Correct	5 ms	4184 KB	Output is correct
6	Correct	5 ms	4184 KB	Output is correct
7	Correct	5 ms	4184 KB	Output is correct
8	Correct	4 ms	4184 KB	Output is correct
9	Correct	7 ms	4184 KB	Output is correct
10	Correct	5 ms	4184 KB	Output is correct
11	Correct	6 ms	4184 KB	Output is correct
12	Correct	3 ms	4184 KB	Output is correct
13	Correct	8 ms	4184 KB	Output is correct
14	Correct	3 ms	856 KB	Output is correct
15	Correct	11 ms	4628 KB	Output is correct
16	Correct	2 ms	4184 KB	Output is correct
17	Correct	5 ms	4184 KB	Output is correct
18	Partially correct	35 ms	4440 KB	Partially correct - number of queries: 5046
19	Correct	6 ms	4184 KB	Output is correct
20	Correct	9 ms	2392 KB	Output is correct
21	Correct	17 ms	4360 KB	Output is correct
22	Correct	7 ms	4372 KB	Output is correct
23	Correct	5 ms	4372 KB	Output is correct
24	Correct	8 ms	4184 KB	Output is correct
25	Correct	17 ms	4184 KB	Output is correct
26	Correct	14 ms	4184 KB	Output is correct
27	Correct	7 ms	4444 KB	Output is correct
28	Correct	18 ms	4184 KB	Output is correct
29	Correct	17 ms	4184 KB	Output is correct
30	Correct	26 ms	4356 KB	Output is correct
31	Correct	5 ms	4380 KB	Output is correct
32	Correct	6 ms	4440 KB	Output is correct
33	Correct	1 ms	344 KB	Output is correct
34	Correct	11 ms	4184 KB	Output is correct
35	Correct	6 ms	4184 KB	Output is correct
36	Correct	9 ms	4184 KB	Output is correct
37	Correct	6 ms	4184 KB	Output is correct
38	Correct	5 ms	4184 KB	Output is correct
39	Correct	16 ms	4184 KB	Output is correct
40	Correct	23 ms	4432 KB	Output is correct
41	Correct	18 ms	4440 KB	Output is correct
42	Correct	16 ms	4432 KB	Output is correct
43	Correct	15 ms	4432 KB	Output is correct
44	Correct	13 ms	4184 KB	Output is correct
45	Correct	9 ms	4184 KB	Output is correct
46	Correct	5 ms	4184 KB	Output is correct
47	Correct	13 ms	4184 KB	Output is correct
48	Correct	19 ms	4368 KB	Output is correct
49	Correct	6 ms	4184 KB	Output is correct
50	Partially correct	25 ms	4356 KB	Partially correct - number of queries: 5045
51	Correct	16 ms	4184 KB	Output is correct
52	Correct	5 ms	4184 KB	Output is correct
53	Correct	5 ms	4184 KB	Output is correct
54	Correct	14 ms	4184 KB	Output is correct
55	Correct	5 ms	4440 KB	Output is correct
56	Partially correct	30 ms	4432 KB	Partially correct - number of queries: 5068
57	Correct	14 ms	4184 KB	Output is correct
58	Correct	24 ms	4356 KB	Output is correct
59	Correct	19 ms	4184 KB	Output is correct
60	Correct	14 ms	4184 KB	Output is correct
61	Correct	5 ms	4384 KB	Output is correct
62	Correct	5 ms	4184 KB	Output is correct
63	Correct	5 ms	4184 KB	Output is correct
64	Correct	5 ms	4184 KB	Output is correct
65	Correct	4 ms	4184 KB	Output is correct
66	Correct	4 ms	4184 KB	Output is correct
67	Correct	7 ms	4184 KB	Output is correct
68	Correct	5 ms	4184 KB	Output is correct
69	Correct	5 ms	4184 KB	Output is correct
70	Correct	6 ms	4380 KB	Output is correct
71	Partially correct	39 ms	4376 KB	Partially correct - number of queries: 5477
72	Correct	7 ms	4184 KB	Output is correct
73	Partially correct	28 ms	4184 KB	Partially correct - number of queries: 5416
74	Partially correct	20 ms	4184 KB	Partially correct - number of queries: 5443
75	Correct	7 ms	4440 KB	Output is correct
76	Correct	27 ms	4184 KB	Output is correct
77	Partially correct	29 ms	4184 KB	Partially correct - number of queries: 5167
78	Correct	7 ms	4380 KB	Output is correct
79	Correct	20 ms	4184 KB	Output is correct
80	Partially correct	27 ms	4432 KB	Partially correct - number of queries: 5196
81	Partially correct	23 ms	4432 KB	Partially correct - number of queries: 5196
82	Partially correct	22 ms	4184 KB	Partially correct - number of queries: 5129
83	Correct	7 ms	4380 KB	Output is correct
84	Correct	22 ms	4184 KB	Output is correct
85	Partially correct	34 ms	4440 KB	Partially correct - number of queries: 5138
86	Correct	7 ms	4440 KB	Output is correct
87	Correct	4 ms	4184 KB	Output is correct
88	Correct	5 ms	4384 KB	Output is correct
89	Correct	5 ms	4184 KB	Output is correct
90	Correct	6 ms	4184 KB	Output is correct
91	Correct	7 ms	4440 KB	Output is correct
92	Correct	4 ms	4184 KB	Output is correct
93	Correct	4 ms	4384 KB	Output is correct
94	Correct	6 ms	4184 KB	Output is correct
95	Correct	6 ms	4184 KB	Output is correct
96	Correct	6 ms	4456 KB	Output is correct
97	Correct	5 ms	4440 KB	Output is correct