Submission #619014

#	Time	Username	Problem	Language	Result	Execution time	Memory
619014		Zanite	Xoractive (IZhO19_xoractive)	C++17	100 / 100	5 ms	592 KiB

Xoractive

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

vector<int> ans;
map<int, int> pos;

vector<int> guess(int n) {
	ans.assign(n, 0);
	ans[0] = ask(1);

	int logN = 31 - __builtin_clz(n);
	//cerr << logN << '\n';
	for (int b = 0; b <= logN; b++) {
		cerr << b << '\n';
		// get the values of ans[0] ^ ... for the indices whose b-th bit is on
		// by inserting 1 to said set of indices
		multiset<int> bitval;

		vector<int> toQuery, queryAns;
		for (int i = 2; i <= n; i++) {
			if (i & (1 << b)) {toQuery.push_back(i);}
		}

		toQuery.push_back(1);
		queryAns = get_pairwise_xor(toQuery);
		for (auto &i : queryAns) {bitval.insert(i);}

		toQuery.pop_back();
		queryAns = get_pairwise_xor(toQuery);
		for (auto &i : queryAns) {bitval.erase(bitval.lower_bound(i));}

		//for (auto &i : bitval) {cout << i << ' ';} cout << '\n';

		// remove 0 because all elements are distinct
		bitval.erase(0);

		for (auto &i : bitval) {
			pos[i ^ ans[0]] |= (1 << b);
			//cout << (i ^ ans[0]) << ' ' << b << '\n';
		}
	}

	for (auto &[val, idx] : pos) {
		ans[idx-1] = val;
	}
	
	//for (auto &i : ans) cout << i << ' '; cout << '\n';
	return ans;
}

// Grader
#ifdef Zanite
namespace {
    const int MAX_VALUE_OF_N = 100;
    const int MAX_VALUE_OF_Q = 200;
    int numberOfQueries = 0;
    int n;
    std::vector<int> a;

    void wrong_answer(const char *MSG) {
        printf("-1\n");
        exit(0);
    }
}

void query() {
    numberOfQueries++;

    if (numberOfQueries > MAX_VALUE_OF_Q) {
        wrong_answer("Number of queries exceeded");
    }
}

int ask(int position) {
    query();
    
    if (position < 1 || position > n) {
        wrong_answer("Not correct position");
    }
    return a[position - 1];

}
vector<int> get_pairwise_xor(vector<int> positions) {
    query();
    
    if (positions.empty() || positions.size() > n) {
        wrong_answer("Not correct size");
    }
    
    sort(positions.begin(), positions.end());
    
    for (int i = 1; i < positions.size(); i++) {
        if (positions[i] == positions[i - 1]) {
            wrong_answer("Not unique");
        }
    }

    for (int i = 0; i < positions.size(); i++) {
        if (positions[i] < 1 || positions[i] > n) {
            wrong_answer("Not correct position");
        }
    }

    vector<int> pairwise_xor;
    
    for (int i = 0; i < positions.size(); i++) {
        for (int j = 0; j < positions.size(); j++) {
            pairwise_xor.push_back(a[positions[i] - 1] ^ a[positions[j] - 1]);
        }
    }
    sort(pairwise_xor.begin(), pairwise_xor.end());

    return pairwise_xor;
}

int main() {
    assert(scanf("%d", &n) == 1);

    assert(1 <= n && n <= MAX_VALUE_OF_N);
    
    for (int i = 1; i <= n; i++) {
        int x;

        assert(scanf("%d", &x) == 1);
        assert(x >= 0 && x <= 1000 * 1000 * 1000);

        a.push_back(x);
    }
    vector<int> participant_solution = guess(n);

    if (participant_solution.size() != n) {
        wrong_answer("-1");
    }

	printf("%d\n", n);
    
    for (auto i: participant_solution) {
        printf("%d ", i);
    }
    printf("\n");
    printf("%d\n", numberOfQueries);
    return 0;
}
#endif

• Subtask 1: 6 / 6
• Subtask 2: 94 / 94