Submission #925568

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
925568	2024-02-12T05:19:33 Z	ttamx	Ancient Machine 2 (JOI23_ancient2)	C++17	100 / 100	43 ms	2196 KB

ancient2

#include "ancient2.h"
#include<bits/stdc++.h>

using namespace std;

const int N=1000;
const int Q=102;

using BS = bitset<N>;
using VBS = vector<BS>;

struct Basis{
	VBS basis;
	int n,cnt;
	Basis(){}
	Basis(int _n){
		init(_n);
	}
	void init(int _n){
		n=_n;
		cnt=0;
		basis.assign(_n,BS{});
	}
	bool insert(BS v){
		for(int i=0;i<n;i++){
			if(v[i]){
				if(basis[i][i]){
					v^=basis[i];
				}else{
					basis[i]=v;
					cnt++;
					return true;
				}
			}
		}
		return false;
	}
};

void gaussian_elimation(int n,VBS &a,vector<int> &b){
	for(int i=0;i<n;i++){
		int id=i;
		while(!a[id][i])id++;
		swap(a[i],a[id]);
		swap(b[i],b[id]);
		for(int j=0;j<n;j++)if(i!=j&&a[j][i]){
			a[j]^=a[i];
			b[j]^=b[i];
		}
	}
}

bool ask(int n,int m,int r){
	vector<int> a(m*2),b(m*2);
	for(int i=0;i<m;i++){
		int p=(i+1)%m;
		a[i]=b[i]=p;
		a[i+m]=b[i+m]=p+m;
	}
	int p=(r+1)%m;
	b[r]=m+p;
	b[r+m]=p;
	return Query(2*m,a,b)>=m;
}

vector<int> solve_left(int n){
	vector<int> ans(n);
	int m=n+2;
	vector<int> a(m),b(m);
	a[n]=b[n]=n;
	a[n+1]=b[n+1]=n+1;
	for(int i=0;i<n;i++){
		a[i]=n;
		b[i]=n+1;
	}
	for(int i=0;i<n;i++){
		int res=Query(m,a,b);
		ans[i]=res-n;
		a[i]=b[i]=i+1;
	}
	return ans;
}

vector<int> solve_right(int n){
	vector<int> ans;
	for(int i=0;i<n;i++){
		ans.insert(ans.begin(),1);
		int m=i+2;
		vector<vector<int>> a(2,vector<int>(m));
		for(int j=0;j<m;j++){
			for(int c=0;c<2;c++){
				int sz=min(j+1,i+1);
				while(sz>0){
					vector<int> res(ans.begin()+j-sz+1,ans.begin()+j);
					res.emplace_back(c);
					vector<int> res2(ans.begin(),ans.begin()+sz);
					if(res==res2)break;
					sz--;
				}
				a[c][j]=sz;
			}
		}
		ans[0]=Query(m,a[0],a[1])==i+1;
	}
	return ans;
}

string Solve(int n) {
	Basis basis(n);
	VBS mat;
	vector<int> ans;
	auto vl=solve_left(min(n/2,Q-2));
	for(int i=0;i<vl.size();i++){
		BS res;
		res[i]=true;
		if(basis.insert(res)){
			mat.emplace_back(res);
			ans.emplace_back(vl[i]);
			if(basis.cnt==n)break;
		}
	}
	auto vr=solve_right(min((n+1)/2,Q-1));
	for(int i=0;i<vr.size();i++){
		BS res;
		res[n-vr.size()+i]=true;
		if(basis.insert(res)){
			mat.emplace_back(res);
			ans.emplace_back(vr[i]);
			if(basis.cnt==n)break;
		}
	}
	for(int m=2;m<=Q/2;m++){
		for(int r=0;r<m;r++){
			BS res;
			for(int i=r;i<n;i+=m)res[i]=true;
			if(basis.insert(res)){
				mat.emplace_back(res);
				ans.emplace_back(ask(n,m,r));
				if(basis.cnt==n)break;
 			}
		}
		if(basis.cnt==n)break;
	}
	gaussian_elimation(n,mat,ans);
	string res="";
	for(auto x:ans)res.push_back('0'+x);
	return res;
}

Compilation message

ancient2.cpp: In function 'std::string Solve(int)':
ancient2.cpp:113:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  113 |  for(int i=0;i<vl.size();i++){
      |              ~^~~~~~~~~~
ancient2.cpp:123:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  123 |  for(int i=0;i<vr.size();i++){
      |              ~^~~~~~~~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	38 ms	1152 KB	Output is correct
2	Correct	35 ms	1120 KB	Output is correct
3	Correct	39 ms	1736 KB	Output is correct
4	Correct	39 ms	1484 KB	Output is correct
5	Correct	34 ms	1888 KB	Output is correct
6	Correct	35 ms	1432 KB	Output is correct
7	Correct	35 ms	1428 KB	Output is correct
8	Correct	35 ms	900 KB	Output is correct
9	Correct	35 ms	1688 KB	Output is correct
10	Correct	36 ms	1668 KB	Output is correct
11	Correct	35 ms	1020 KB	Output is correct
12	Correct	36 ms	1972 KB	Output is correct
13	Correct	36 ms	1520 KB	Output is correct
14	Correct	34 ms	956 KB	Output is correct
15	Correct	35 ms	1340 KB	Output is correct
16	Correct	35 ms	1116 KB	Output is correct
17	Correct	38 ms	1408 KB	Output is correct
18	Correct	41 ms	1228 KB	Output is correct
19	Correct	34 ms	1112 KB	Output is correct
20	Correct	35 ms	1872 KB	Output is correct
21	Correct	37 ms	1104 KB	Output is correct
22	Correct	35 ms	860 KB	Output is correct
23	Correct	34 ms	1228 KB	Output is correct
24	Correct	35 ms	1780 KB	Output is correct
25	Correct	36 ms	1860 KB	Output is correct
26	Correct	35 ms	1644 KB	Output is correct
27	Correct	36 ms	1372 KB	Output is correct
28	Correct	41 ms	1868 KB	Output is correct
29	Correct	38 ms	1328 KB	Output is correct
30	Correct	35 ms	1412 KB	Output is correct
31	Correct	36 ms	1460 KB	Output is correct
32	Correct	37 ms	1664 KB	Output is correct
33	Correct	36 ms	1960 KB	Output is correct
34	Correct	38 ms	1464 KB	Output is correct
35	Correct	37 ms	812 KB	Output is correct
36	Correct	37 ms	1656 KB	Output is correct
37	Correct	38 ms	1640 KB	Output is correct
38	Correct	37 ms	1904 KB	Output is correct
39	Correct	35 ms	1092 KB	Output is correct
40	Correct	36 ms	2008 KB	Output is correct
41	Correct	35 ms	1324 KB	Output is correct
42	Correct	36 ms	1400 KB	Output is correct
43	Correct	34 ms	1492 KB	Output is correct
44	Correct	35 ms	1500 KB	Output is correct
45	Correct	37 ms	2196 KB	Output is correct
46	Correct	37 ms	1356 KB	Output is correct
47	Correct	40 ms	1344 KB	Output is correct
48	Correct	36 ms	1448 KB	Output is correct
49	Correct	39 ms	848 KB	Output is correct
50	Correct	35 ms	1400 KB	Output is correct
51	Correct	37 ms	1956 KB	Output is correct
52	Correct	35 ms	1496 KB	Output is correct
53	Correct	35 ms	1276 KB	Output is correct
54	Correct	37 ms	1868 KB	Output is correct
55	Correct	37 ms	1060 KB	Output is correct
56	Correct	37 ms	1972 KB	Output is correct
57	Correct	38 ms	1372 KB	Output is correct
58	Correct	35 ms	1344 KB	Output is correct
59	Correct	35 ms	1156 KB	Output is correct
60	Correct	43 ms	1620 KB	Output is correct
61	Correct	34 ms	860 KB	Output is correct
62	Correct	35 ms	1356 KB	Output is correct
63	Correct	35 ms	1144 KB	Output is correct