oj.uz

Submission #949144

# Submission time Handle Problem Language Result Execution time Memory
949144 2024-03-19T02:23:17 Z koukirocks Love Polygon (BOI18_polygon) C++17
46 / 100
 133 ms 21508 KB 
#include <bits/stdc++.h>
#define speed ios_base::sync_with_stdio(0); cin.tie(0)
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
 
using namespace std;
typedef long long ll;
typedef double db;
typedef long double ldb;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
 
const ll MAX=1e5+10,P=998244353;
const ll INF=0x3f3f3f3f,oo=0x3f3f3f3f3f3f3f3f;

int n;
vector<pair<string,string> > eg;
int G[MAX];
vector<int> cptG[MAX];

void dfs(int v,int p,vector<int>& sz) {
	sz[v]=1;
	for (int i:cptG[v]) {
		if (i==p) continue;
		dfs(i,v,sz);
		sz[v]+=sz[i];
	}
}

int dfs2(int v,int p,bool can,vector<int>& sz) {
//	cout<<v<<" "<<p<<" "<<can<<"\n";
	if (sz[v]==1) return can;
	int ans=0;
	int minn=INF;
	int id=0;
	if (can) {
		for (int i:cptG[v]) {
			if (i==p) continue;
			if (sz[i]<minn) {
				minn=sz[i];
				id=i;
			}
		}
		ans+=dfs2(id,v,0,sz)+1;
	}
	for (int i:cptG[v]) {
		if (i==p) continue;
		if (can and i==id) continue;
		ans+=dfs2(i,v,1,sz);
	}
	return ans;
}

int main() {
	speed;
	cin>>n;
	vector<string> dct;
	for (int i=0;i<n;i++) {
		string a,b;
		cin>>a>>b;
		eg.emplace_back(a,b);
		dct.push_back(a);
		dct.push_back(b);
	}
	sort(all(dct));
	dct.resize(unique(all(dct))-dct.begin());
	vector<int> lvd(n,0);
	for (int i=0;i<n;i++) {
		auto [a,b]=eg[i];
		int va=lower_bound(all(dct),a)-dct.begin();
		int vb=lower_bound(all(dct),b)-dct.begin();
		G[va]=vb;
		cptG[va].push_back(vb);
		cptG[vb].push_back(va);
		lvd[vb]++;
	}
	bool alllvd=true;
	for (int i=0;i<n;i++) {
		if (lvd[i]!=1) {
			alllvd=false;
			break;
		}
	}
	if (n&1) {
		cout<<"-1\n";
		return 0;
	}
	if (n<=20) {
		int ans=n;
		for (int st=0;st<(1<<n);st++) {
			bool flag=true;
			vector<int> cnt(n,0);
			for (int i=0;i<n;i++) {
				if (st&(1<<i)) continue;
				if (G[i]==i) {
					flag=false;
					break;
				}
				int tgt=G[i];
				if (G[tgt]==i) continue;
				if (st&(1<<tgt)) {
					if (cnt[tgt]==0) {
						cnt[tgt]++;
						continue;
					}
				}
				flag=false;
				break;
			}
	//		if (flag) cout<<st<<"\n";
			if (flag) ans=min(ans,__builtin_popcount(st));
		}
		cout<<ans<<"\n";
	} else if (alllvd) {
		vector<bool> vis(n,0);
		int ans=0;
		for (int i=0;i<n;i++) {
			if (vis[i]) continue;
			int now=i;
			int st=i;
			int sz=1;
			vis[i]=true;
			while (G[now]!=st) {
//				cout<<now<<" ";
				sz++;
				now=G[now];
				vis[now]=true;
			}
			if (sz==2) continue;
			ans+=(sz+1)>>1;
		}
		cout<<ans<<"\n";
	} else {
		vector<int> sz(n);
		int ans=0;
		for (int i=0;i<n;i++) {
			if (G[i]==i) {
				dfs(i,i,sz);
				ans+=dfs2(i,i,1,sz);
			}
		}
		cout<<ans<<"\n";
	}
	return 0;
}

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 27 ms 2652 KB Output is correct
2 Correct 21 ms 2648 KB Output is correct
3 Correct 25 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2652 KB Output is correct
6 Correct 1 ms 2652 KB Output is correct
7 Correct 26 ms 2652 KB Output is correct
8 Correct 27 ms 2652 KB Output is correct
9 Correct 22 ms 2648 KB Output is correct
10 Correct 29 ms 2816 KB Output is correct
11 Correct 29 ms 2816 KB Output is correct
12 Correct 2 ms 2652 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 2 ms 2652 KB Output is correct
15 Correct 1 ms 2652 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 122 ms 21508 KB Output is correct
5 Correct 133 ms 19332 KB Output is correct
6 Correct 125 ms 20428 KB Output is correct
7 Correct 123 ms 20212 KB Output is correct

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 122 ms 20908 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 27 ms 2652 KB Output is correct
2 Correct 21 ms 2648 KB Output is correct
3 Correct 25 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2652 KB Output is correct
6 Correct 1 ms 2652 KB Output is correct
7 Correct 26 ms 2652 KB Output is correct
8 Correct 27 ms 2652 KB Output is correct
9 Correct 22 ms 2648 KB Output is correct
10 Correct 29 ms 2816 KB Output is correct
11 Correct 29 ms 2816 KB Output is correct
12 Correct 2 ms 2652 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 2 ms 2652 KB Output is correct
15 Correct 1 ms 2652 KB Output is correct
16 Correct 1 ms 2652 KB Output is correct
17 Correct 1 ms 2652 KB Output is correct
18 Correct 1 ms 2652 KB Output is correct
19 Correct 122 ms 21508 KB Output is correct
20 Correct 133 ms 19332 KB Output is correct
21 Correct 125 ms 20428 KB Output is correct
22 Correct 123 ms 20212 KB Output is correct
23 Incorrect 122 ms 20908 KB Output isn't correct
24 Halted 0 ms 0 KB -