Submission #957016

#	Time	Username	Problem	Language	Result	Execution time	Memory
957016		pragmatist	Xoractive (IZhO19_xoractive)	C++17	80 / 100	4 ms	756 KiB

Xoractive

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

vector<int> guess(int n) {
	vector<int> ans(n+1, -1);
	map<int, int> cnt[10];
	for(int i = 0; (1<<i) <= n; ++i) {
		vector<int> ind;
		for(int j = 1; j <= n; ++j) {
			if(j >> i & 1) {
				ind.push_back(j);
			}
		}
		assert(!ind.empty());
		for(int j = 0; j < (int)ind.size(); ++j) {
			if(ans[ind[j]] != -1) {
				ind.insert(ind.begin(), ind[j]);
				ind.erase(ind.begin()+j+1);
				break;
			}
		}
		if(ans[ind[0]] == -1) {
			ans[ind[0]] = ask(ind[0]);
		}
		int st = ans[ind[0]];
		if((int)ind.size()== 1) {
			continue;
		}
		map<int, int> cur;
		vector<int> c1 = get_pairwise_xor(ind);
		for(auto x : c1) {
			cur[x]++;
		}
		ind.erase(ind.begin());
		if((int)ind.size() == 2) {
			ans[ind[0]] = (c1.back()^st);
			continue;
		}
		vector<int> c2 = get_pairwise_xor(ind);
		for(auto x : c2) {
			cur[x]--;
		}
		vector<int> v;
		for(auto e : cur) {
			if(e.second == 0) {
				continue;
			}
			v.push_back(e.first^st);
		}
		for(auto x : v) {
			cnt[i][x]++;
		}
	}
	for(int i = n; i >= 1; --i) {
		if(ans[i] != -1) {
			continue;
		}
		map<int, int> cur;
		int tot = 0;
		for(int j = 0; (1 << j) <= i; ++j) {
			if(i >> j & 1) {
				tot++;
				for(auto e : cnt[j]) {
					cur[e.first]++;
				}
			}
		}
		for(auto e : cur) {
			if(e.second == tot) {
				ans[i] = e.first;
			}
		}
		for(int j = 0; (1 << j) <= i; ++j) {
			if(i >> j & 1) {
				cnt[j].erase(ans[i]);
			}
		}
	}
	ans.erase(ans.begin());
	return ans;
}

• Subtask 1: 6 / 6
• Subtask 2: 74 / 94