oj.uz

Submission #1108541

# Submission time Handle Problem Language Result Execution time Memory
1108541 2024-11-04T11:32:49 Z _rain_ Love Polygon (BOI18_polygon) C++14
75 / 100
 173 ms 145920 KB 
#include<bits/stdc++.h>
using namespace std;
 
typedef long long ll;
#define name "main"
 
const int N=(int)1e6;
vector<string>nen;
string s1[N+2],s2[N+2];
int deg[N+2],num[N+2],low[N+2],id[N+2],scc=0,timedfs=0;
int u[N+2],v[N+2],to[N+2],dp[N+2][2],n;
vector<int>ord,bag[N+2],ke[N+2];
bool used[N+2],del[N+2];
 
void buildup(int u){
	num[u]=low[u]=++timedfs;
	ord.push_back(u);
	
	if (!num[to[u]]&&!del[to[u]]){
		buildup(to[u]);
		low[u]=min(low[u],low[to[u]]);
	}
	else if (!del[to[u]]) low[u]=min(low[u],num[to[u]]);
	if (low[u]==num[u]){
		int v;
		++scc;
		do{
			v=ord.back();
			ord.pop_back();
			id[v]=scc;
			del[v]=true;
			bag[id[v]].push_back(v);
		}while(v!=u);
	}
}
void dfs(int u){
	if (ke[u].size()==0){
		dp[u][0]=0;
		dp[u][1]=1;
		return;
	}
	for(auto&v:ke[u]){
		dfs(v);
		dp[u][1]+=dp[v][0];
	}
	dp[u][1]++;
	for(auto&v:ke[u]){
		dp[u][0]=max(dp[u][0],dp[u][1]-1+max(0,dp[v][1]-dp[v][0]));
	}
}
 
int32_t main(){
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	cin>>n;
	if (n%2==1){
		cout<<-1;
		exit(0);
	}
	map<string,int> mp;
	int cn=0;
	for(int i=1;i<=n;++i){
		string s1,s2; cin>>s1>>s2;
		if (mp.find(s1)==mp.end()) mp[s1]=++cn;
		if (mp.find(s2)==mp.end()) mp[s2]=++cn;
		u[i]=mp[s1];
		v[i]=mp[s2];
		to[u[i]]=v[i];
	}
	for(int i=1;i<=n;++i) if (!num[i]) buildup(i);
	for(int i=1;i<=scc;++i){
		for(auto&u:bag[i]){
			if (id[to[u]]!=i){
				ke[id[to[u]]].push_back(i);
				deg[i]++;
			}
		}
	}
	for(int i=1;i<=scc;++i) {
		sort(ke[i].begin(),ke[i].end());
		ke[i].resize(unique(ke[i].begin(),ke[i].end())-ke[i].begin());
	}
	int ans=0;
	// for(int i=1;i<=n;++i){
	// 	cout<<u[i]<<' '<<v[i]<<'\n';
	// }
	// for(int i=1;i<=n;++i) cout<<id[i]<<' '; cout<<'\n';
	for(int i=1;i<=scc;++i){
		if (deg[i]==0){
			dfs(i);
			if (bag[i].size()==2) ans+=2; else ans+=bag[i].size()/2;
			if (bag[i].size()%2==0) ans+=dp[i][1]-1; else ans+=dp[i][0];
		}
	}
	cout<<n-ans;
	exit(0);
}

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 124508 KB Output is correct
2 Correct 22 ms 124496 KB Output is correct
3 Correct 21 ms 124496 KB Output is correct
4 Correct 21 ms 124496 KB Output is correct
5 Correct 19 ms 114124 KB Output is correct
6 Correct 19 ms 114000 KB Output is correct
7 Correct 21 ms 122448 KB Output is correct
8 Correct 20 ms 124504 KB Output is correct
9 Correct 19 ms 124664 KB Output is correct
10 Correct 22 ms 124496 KB Output is correct
11 Correct 21 ms 124496 KB Output is correct
12 Correct 20 ms 124512 KB Output is correct
13 Correct 22 ms 124496 KB Output is correct
14 Correct 20 ms 124496 KB Output is correct
15 Correct 21 ms 124496 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 122372 KB Output is correct
2 Correct 20 ms 122448 KB Output is correct
3 Correct 20 ms 122388 KB Output is correct
4 Correct 162 ms 139000 KB Output is correct
5 Correct 162 ms 132040 KB Output is correct
6 Correct 163 ms 139916 KB Output is correct
7 Correct 19 ms 114000 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 170 ms 140616 KB Output is correct
2 Correct 171 ms 142408 KB Output is correct
3 Correct 149 ms 136208 KB Output is correct
4 Correct 20 ms 114000 KB Output is correct
5 Correct 173 ms 145920 KB Output is correct
6 Correct 172 ms 139848 KB Output is correct
7 Correct 166 ms 139848 KB Output is correct
8 Correct 161 ms 139428 KB Output is correct
9 Correct 157 ms 139496 KB Output is correct
10 Correct 125 ms 138696 KB Output is correct
11 Correct 21 ms 124496 KB Output is correct
12 Correct 20 ms 124508 KB Output is correct
13 Correct 21 ms 124496 KB Output is correct
14 Correct 22 ms 124496 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 124508 KB Output is correct
2 Correct 22 ms 124496 KB Output is correct
3 Correct 21 ms 124496 KB Output is correct
4 Correct 21 ms 124496 KB Output is correct
5 Correct 19 ms 114124 KB Output is correct
6 Correct 19 ms 114000 KB Output is correct
7 Correct 21 ms 122448 KB Output is correct
8 Correct 20 ms 124504 KB Output is correct
9 Correct 19 ms 124664 KB Output is correct
10 Correct 22 ms 124496 KB Output is correct
11 Correct 21 ms 124496 KB Output is correct
12 Correct 20 ms 124512 KB Output is correct
13 Correct 22 ms 124496 KB Output is correct
14 Correct 20 ms 124496 KB Output is correct
15 Correct 21 ms 124496 KB Output is correct
16 Correct 20 ms 122372 KB Output is correct
17 Correct 20 ms 122448 KB Output is correct
18 Correct 20 ms 122388 KB Output is correct
19 Correct 162 ms 139000 KB Output is correct
20 Correct 162 ms 132040 KB Output is correct
21 Correct 163 ms 139916 KB Output is correct
22 Correct 19 ms 114000 KB Output is correct
23 Correct 170 ms 140616 KB Output is correct
24 Correct 171 ms 142408 KB Output is correct
25 Correct 149 ms 136208 KB Output is correct
26 Correct 20 ms 114000 KB Output is correct
27 Correct 173 ms 145920 KB Output is correct
28 Correct 172 ms 139848 KB Output is correct
29 Correct 166 ms 139848 KB Output is correct
30 Correct 161 ms 139428 KB Output is correct
31 Correct 157 ms 139496 KB Output is correct
32 Correct 125 ms 138696 KB Output is correct
33 Correct 21 ms 124496 KB Output is correct
34 Correct 20 ms 124508 KB Output is correct
35 Correct 21 ms 124496 KB Output is correct
36 Correct 22 ms 124496 KB Output is correct
37 Incorrect 169 ms 141148 KB Output isn't correct
38 Halted 0 ms 0 KB -