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Submission #1108531

# Submission time Handle Problem Language Result Execution time Memory
1108531 2024-11-04T11:05:19 Z _rain_ Love Polygon (BOI18_polygon) C++14
75 / 100
 140 ms 35080 KB 
#include<bits/stdc++.h>
using namespace std;
 
typedef long long ll;
#define name "main"
 
const int N=(int)1e5;
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);
	}
	for(int i=1;i<=n;++i){
		cin>>s1[i]>>s2[i];
		nen.push_back(s1[i]);
		nen.push_back(s2[i]);
	}
	sort(nen.begin(),nen.end());
	nen.resize(unique(nen.begin(),nen.end())-nen.begin());
	for(int i=1;i<=n;++i){
		u[i]=upper_bound(nen.begin(),nen.end(),s1[i])-nen.begin();
		v[i]=upper_bound(nen.begin(),nen.end(),s2[i])-nen.begin();
		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 3 ms 14928 KB Output is correct
2 Correct 2 ms 14928 KB Output is correct
3 Correct 3 ms 15096 KB Output is correct
4 Correct 2 ms 15096 KB Output is correct
5 Correct 2 ms 12880 KB Output is correct
6 Correct 2 ms 13052 KB Output is correct
7 Correct 2 ms 14928 KB Output is correct
8 Correct 3 ms 15096 KB Output is correct
9 Correct 3 ms 14928 KB Output is correct
10 Correct 3 ms 14928 KB Output is correct
11 Correct 2 ms 14928 KB Output is correct
12 Correct 2 ms 14928 KB Output is correct
13 Correct 2 ms 14928 KB Output is correct
14 Correct 2 ms 14928 KB Output is correct
15 Correct 2 ms 14928 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 15096 KB Output is correct
2 Correct 3 ms 14928 KB Output is correct
3 Correct 3 ms 15184 KB Output is correct
4 Correct 121 ms 33264 KB Output is correct
5 Correct 115 ms 26288 KB Output is correct
6 Correct 119 ms 34480 KB Output is correct
7 Correct 3 ms 12880 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 140 ms 28592 KB Output is correct
2 Correct 125 ms 30464 KB Output is correct
3 Correct 100 ms 26356 KB Output is correct
4 Correct 3 ms 12880 KB Output is correct
5 Correct 126 ms 35080 KB Output is correct
6 Correct 120 ms 27912 KB Output is correct
7 Correct 122 ms 27824 KB Output is correct
8 Correct 118 ms 27396 KB Output is correct
9 Correct 115 ms 27396 KB Output is correct
10 Correct 86 ms 27056 KB Output is correct
11 Correct 3 ms 14928 KB Output is correct
12 Correct 2 ms 14928 KB Output is correct
13 Correct 3 ms 14928 KB Output is correct
14 Correct 3 ms 14928 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14928 KB Output is correct
2 Correct 2 ms 14928 KB Output is correct
3 Correct 3 ms 15096 KB Output is correct
4 Correct 2 ms 15096 KB Output is correct
5 Correct 2 ms 12880 KB Output is correct
6 Correct 2 ms 13052 KB Output is correct
7 Correct 2 ms 14928 KB Output is correct
8 Correct 3 ms 15096 KB Output is correct
9 Correct 3 ms 14928 KB Output is correct
10 Correct 3 ms 14928 KB Output is correct
11 Correct 2 ms 14928 KB Output is correct
12 Correct 2 ms 14928 KB Output is correct
13 Correct 2 ms 14928 KB Output is correct
14 Correct 2 ms 14928 KB Output is correct
15 Correct 2 ms 14928 KB Output is correct
16 Correct 3 ms 15096 KB Output is correct
17 Correct 3 ms 14928 KB Output is correct
18 Correct 3 ms 15184 KB Output is correct
19 Correct 121 ms 33264 KB Output is correct
20 Correct 115 ms 26288 KB Output is correct
21 Correct 119 ms 34480 KB Output is correct
22 Correct 3 ms 12880 KB Output is correct
23 Correct 140 ms 28592 KB Output is correct
24 Correct 125 ms 30464 KB Output is correct
25 Correct 100 ms 26356 KB Output is correct
26 Correct 3 ms 12880 KB Output is correct
27 Correct 126 ms 35080 KB Output is correct
28 Correct 120 ms 27912 KB Output is correct
29 Correct 122 ms 27824 KB Output is correct
30 Correct 118 ms 27396 KB Output is correct
31 Correct 115 ms 27396 KB Output is correct
32 Correct 86 ms 27056 KB Output is correct
33 Correct 3 ms 14928 KB Output is correct
34 Correct 2 ms 14928 KB Output is correct
35 Correct 3 ms 14928 KB Output is correct
36 Correct 3 ms 14928 KB Output is correct
37 Incorrect 127 ms 31344 KB Output isn't correct
38 Halted 0 ms 0 KB -