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Submission #829823

# Submission time Handle Problem Language Result Execution time Memory
829823 2023-08-18T15:15:37 Z Darren0724 Love Polygon (BOI18_polygon) C++17
0 / 100
 148 ms 9228 KB 
#include<bits/stdc++.h>
using namespace std;
const int N=100005;
map<string,int> m;
vector<int> vis(N);
vector<int> v(N),in(N);
int cnt=0;
int id(string s){
    if(m.count(s)){
        return m[s];
    }
    int p=m.size();
    m[s]=p;
    return p;
}

void dfs(int k){
    vis[k]=1;
    cnt++;
    if(!vis[v[k]]){
        dfs(v[k]);
    }
}
int32_t main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;cin>>n;
    if(n&1){
        cout<<-1<<endl;
        return 0;
    }
    for(int i=0;i<n;i++){
        string a,b;cin>>a>>b;
        v[id(a)]=id(b);
        in[id(b)]++;
    }
    int ans=0;
    for(int i=0;i<n;i++){
        if(!vis[i]&&v[v[i]]==i&&v[i]!=i){
            vis[i]=1;
            vis[v[i]]=1;
        }
    }
    for(int i=0;i<n;i++){
        if(in[i]==0&&vis[i]==0){
            cnt=0;
            dfs(i);
            ans+=(cnt+1)/2;
        }
    }
    for(int i=0;i<n;i++){
        if(!vis[i]&&v[i]==i){
            ans++;
        }
    }
    cout<<ans<<endl;

    return 0;
}

Subtask #1
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1492 KB Output is correct
2 Correct 1 ms 1492 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Incorrect 1 ms 1492 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1492 KB Output is correct
2 Correct 1 ms 1508 KB Output is correct
3 Incorrect 1 ms 1508 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 148 ms 9228 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1492 KB Output is correct
2 Correct 1 ms 1492 KB Output is correct
3 Correct 1 ms 1492 KB Output is correct
4 Incorrect 1 ms 1492 KB Output isn't correct
5 Halted 0 ms 0 KB -