Submission #565321

#	Time	Username	Problem	Language	Result	Execution time	Memory
565321		hoanghq2004	The Big Prize (IOI17_prize)	C++14	0 / 100	3 ms	5668 KiB

prize

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include "prize.h"

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;

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 find_best(int n) {
    int tot = 0;
    srand(time(nullptr));
    int m = min(n, 10);
    vector <int> used(n, 0);
    vector <vector <int>> ans(n);
    int res = -1;
    auto get = [&](int i) {
        if (ans[i].size()) return ans[i];
        ans[i] = ask(i);
        if (ans[i][0] + ans[i][1] == 0) {
            res = i;
        }
        return ans[i];
    };
    auto ok = [&](int i) {
        return (get(i)[0] + get(i)[1] == tot);
    };
    while (m--) {
        int i = rand() % n;
        while (used[i]) i = rand() % n;
        used[i] = 1;
        vector <int> cur = get(i);
        tot = max(tot, cur[0] + cur[1]);
    }
    get(0), get(n - 1);
    function <void(int, int, int)> divide = [&](int L, int R, int cnt) {
        if (L > R || cnt <= 0 || res != -1) return;
        int m1 = L + R >> 1;
        int m2 = m1 + 1;
        while (m1 >= L && ok(m1)) --m1;
        while (m2 <= R && ok(m2)) ++m2;
        divide(L, m1, get(m1)[0] - get(L)[0]);
        divide(m2, R, get(m2)[1] - get(R)[1]);
    };
    return res;
}

//
//int main() {
//	cin >> n;
//
//	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);
//	cout << res << endl << "Query count: " << query_count << endl;
//
//	return 0;
//}

Compilation message (stderr)

prize.cpp: In lambda function:
prize.cpp:66:20: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   66 |         int m1 = L + R >> 1;
      |                  ~~^~~
prize.cpp: At global scope:
prize.cpp:16:12: warning: 'query_count' defined but not used [-Wunused-variable]
   16 | static int query_count = 0;
      |            ^~~~~~~~~~~
prize.cpp:15:12: warning: 'n' defined but not used [-Wunused-variable]
   15 | static int n;
      |            ^

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