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Submission #1108687

# Submission time Handle Problem Language Result Execution time Memory
1108687 2024-11-04T19:04:06 Z _rain_ Love Polygon (BOI18_polygon) C++14
100 / 100
 155 ms 37620 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,int ban){
	if (ke[u].size()==0){
		dp[u][0]=0;
		dp[u][1]=1;
		return;
	}
	dp[u][0]=dp[u][1]=0;
	for(auto&v:ke[u]){
		if (v==ban) continue;
		dfs(v,ban);
		dp[u][1]+=dp[v][0];
	}
	dp[u][1]++;
	for(auto&v:ke[u]){
		if (v==ban) continue;
		dp[u][0]=max(dp[u][0],dp[u][1]-1+max(0,dp[v][1]-dp[v][0]));
	}
}
 
int tinhdfs(int u){
	if (bag[u].size()==1){
		dfs(bag[u][0],-1);
		return dp[bag[u][0]][0];
	}
	if (bag[u].size()==2){
		int ans=2;
		int x1=bag[u][0],x2=bag[u][1];
		for(auto&x:ke[x1]) {
			if (x==x2) continue;
			dfs(x,-1);
			ans+=dp[x][0];
		}
		for(auto&x:ke[x2]){
			if (x==x1) continue;
			dfs(x,-1);
			ans+=dp[x][0];
		}
		return ans;
	}
	int w1=1;
	int nn=bag[u][0],tv=to[nn];
	for(auto&v:ke[nn]){
		dfs(v,tv);
		w1+=dp[v][0];
	}
	for(auto&v:ke[tv]){
		if (v==nn) continue;
		dfs(v,nn);
		w1+=dp[v][0];
	}
	dfs(nn,nn);
	int w2=dp[nn][0];
	return max(w1,w2);
}

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];
		if (v[i]!=u[i]) ke[v[i]].push_back(u[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) ++deg[i];
	}
	int ans=0;
	for(int i=1;i<=scc;++i){
		if (deg[i]==0){
			ans+=tinhdfs(i);
		}
	}
	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 3 ms 14928 KB Output is correct
3 Correct 3 ms 14928 KB Output is correct
4 Correct 3 ms 14928 KB Output is correct
5 Correct 3 ms 12880 KB Output is correct
6 Correct 4 ms 12924 KB Output is correct
7 Correct 3 ms 14928 KB Output is correct
8 Correct 4 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 4 ms 14928 KB Output is correct
12 Correct 4 ms 14936 KB Output is correct
13 Correct 3 ms 14928 KB Output is correct
14 Correct 5 ms 15100 KB Output is correct
15 Correct 3 ms 14928 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14928 KB Output is correct
2 Correct 3 ms 14928 KB Output is correct
3 Correct 4 ms 14928 KB Output is correct
4 Correct 150 ms 34224 KB Output is correct
5 Correct 149 ms 29104 KB Output is correct
6 Correct 152 ms 35328 KB Output is correct
7 Correct 3 ms 13048 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 138 ms 30696 KB Output is correct
2 Correct 136 ms 32620 KB Output is correct
3 Correct 98 ms 27992 KB Output is correct
4 Correct 3 ms 12880 KB Output is correct
5 Correct 148 ms 35504 KB Output is correct
6 Correct 133 ms 30128 KB Output is correct
7 Correct 136 ms 29952 KB Output is correct
8 Correct 113 ms 27568 KB Output is correct
9 Correct 122 ms 29464 KB Output is correct
10 Correct 110 ms 26544 KB Output is correct
11 Correct 3 ms 14928 KB Output is correct
12 Correct 3 ms 14928 KB Output is correct
13 Correct 4 ms 14940 KB Output is correct
14 Correct 4 ms 14928 KB Output is correct

Subtask #4
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14928 KB Output is correct
2 Correct 3 ms 14928 KB Output is correct
3 Correct 3 ms 14928 KB Output is correct
4 Correct 3 ms 14928 KB Output is correct
5 Correct 3 ms 12880 KB Output is correct
6 Correct 4 ms 12924 KB Output is correct
7 Correct 3 ms 14928 KB Output is correct
8 Correct 4 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 4 ms 14928 KB Output is correct
12 Correct 4 ms 14936 KB Output is correct
13 Correct 3 ms 14928 KB Output is correct
14 Correct 5 ms 15100 KB Output is correct
15 Correct 3 ms 14928 KB Output is correct
16 Correct 3 ms 14928 KB Output is correct
17 Correct 3 ms 14928 KB Output is correct
18 Correct 4 ms 14928 KB Output is correct
19 Correct 150 ms 34224 KB Output is correct
20 Correct 149 ms 29104 KB Output is correct
21 Correct 152 ms 35328 KB Output is correct
22 Correct 3 ms 13048 KB Output is correct
23 Correct 138 ms 30696 KB Output is correct
24 Correct 136 ms 32620 KB Output is correct
25 Correct 98 ms 27992 KB Output is correct
26 Correct 3 ms 12880 KB Output is correct
27 Correct 148 ms 35504 KB Output is correct
28 Correct 133 ms 30128 KB Output is correct
29 Correct 136 ms 29952 KB Output is correct
30 Correct 113 ms 27568 KB Output is correct
31 Correct 122 ms 29464 KB Output is correct
32 Correct 110 ms 26544 KB Output is correct
33 Correct 3 ms 14928 KB Output is correct
34 Correct 3 ms 14928 KB Output is correct
35 Correct 4 ms 14940 KB Output is correct
36 Correct 4 ms 14928 KB Output is correct
37 Correct 146 ms 31152 KB Output is correct
38 Correct 146 ms 30712 KB Output is correct
39 Correct 130 ms 29560 KB Output is correct
40 Correct 136 ms 30128 KB Output is correct
41 Correct 138 ms 30072 KB Output is correct
42 Correct 129 ms 30320 KB Output is correct
43 Correct 126 ms 30384 KB Output is correct
44 Correct 135 ms 30576 KB Output is correct
45 Correct 136 ms 30384 KB Output is correct
46 Correct 153 ms 30328 KB Output is correct
47 Correct 123 ms 29628 KB Output is correct
48 Correct 131 ms 30896 KB Output is correct
49 Correct 145 ms 32688 KB Output is correct
50 Correct 121 ms 28524 KB Output is correct
51 Correct 3 ms 12880 KB Output is correct
52 Correct 135 ms 37564 KB Output is correct
53 Correct 130 ms 30128 KB Output is correct
54 Correct 117 ms 30128 KB Output is correct
55 Correct 143 ms 29552 KB Output is correct
56 Correct 126 ms 29556 KB Output is correct
57 Correct 83 ms 28792 KB Output is correct
58 Correct 3 ms 14928 KB Output is correct
59 Correct 4 ms 15184 KB Output is correct
60 Correct 3 ms 14928 KB Output is correct
61 Correct 4 ms 14928 KB Output is correct
62 Correct 3 ms 14928 KB Output is correct
63 Correct 3 ms 14928 KB Output is correct
64 Correct 3 ms 14928 KB Output is correct
65 Correct 153 ms 36460 KB Output is correct
66 Correct 155 ms 29104 KB Output is correct
67 Correct 153 ms 37620 KB Output is correct
68 Correct 3 ms 12880 KB Output is correct
69 Correct 3 ms 14928 KB Output is correct
70 Correct 3 ms 14928 KB Output is correct
71 Correct 3 ms 14928 KB Output is correct
72 Correct 3 ms 14928 KB Output is correct
73 Correct 3 ms 12880 KB Output is correct
74 Correct 4 ms 12880 KB Output is correct
75 Correct 3 ms 14928 KB Output is correct
76 Correct 3 ms 14928 KB Output is correct
77 Correct 3 ms 14928 KB Output is correct
78 Correct 3 ms 14968 KB Output is correct
79 Correct 3 ms 14928 KB Output is correct
80 Correct 3 ms 14972 KB Output is correct
81 Correct 3 ms 14928 KB Output is correct
82 Correct 3 ms 14928 KB Output is correct
83 Correct 3 ms 14972 KB Output is correct