oj.uz

Submission #975701

# Submission time Handle Problem Language Result Execution time Memory
975701 2024-05-05T18:15:46 Z Error404 Love Polygon (BOI18_polygon) C++17
0 / 100
 243 ms 26248 KB 
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define f first
#define s second
#define pi pair<int,int>
 
const int MAX = 2e5; 
    
    
int n;
map<string,int>m;
vector<int>g[MAX];
int love[MAX];
int indegree[MAX];
int visited[MAX];
 map<int,string>name;
int main(){
    int n;
    cin>> n;
    string  from, to;
    int k = 1;
    if(n%2){
        cout << -1 << endl;
        return 0;
    }
    int a,b;
    for(int i = 0; i < n; i++){
        cin >> from >> to;
    
        if(m[from]==0) {
           // cout << from << " " << k << endl;
            name[k]=from;
            m[from]=k++;
           
        }
        if(m[to]==0){
           // cout << to << " " << k << endl;
           name[k]=to;
            m[to]=k++;
            
        } 
        a = m[from], b= m[to];
        love[a]=b;
        if(love[b]==a && a!=b){
            visited[a]= visited[b]=1;
        }
        g[a].pb(b);
        indegree[b]++;
    }
    
    
    queue<int>q;
    for(int i = 1; i <= n; i++){
        if(indegree[i]==0 && visited[i]==0){
            q.push(i);
        }
    }
    ll ans = 0;
    while(!q.empty()){
        int from = q.front();
        q.pop();
       //cout <<  name[from] << " " << ans<< endl;
        for(int to : g[from]){
            indegree[to]--;
            if(!visited[to]&&!visited[from]){
                if(visited[from])continue;
                q.push(to);
                
                love[from]=to;
                ans++;
                visited[from]= visited[to] =1;
                
            }
            else if(indegree[to]==0){
                q.push(to);
            }
        }
    }
    
    // ans /=2;
     
     
     
     for(int i = 1; i <= n; i++){
         if(!visited[i] &&!visited[love[i]]&& love[i]!=i && love[i]!=0) {
             ans++;
            visited[i]=1;
            visited[love[i]]=1;
             
         }
     }
     for(int i = 1; i <= n; i++){
         if(!visited[i]) {
             ans++;
            
         }
     }
     
     cout << ans << endl;
     
     
    
    
}

Subtask #1
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7260 KB Output is correct
2 Correct 2 ms 7260 KB Output is correct
3 Correct 1 ms 7260 KB Output is correct
4 Correct 3 ms 7260 KB Output is correct
5 Correct 1 ms 5212 KB Output is correct
6 Correct 1 ms 5212 KB Output is correct
7 Incorrect 2 ms 7260 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7256 KB Output is correct
2 Correct 2 ms 7260 KB Output is correct
3 Correct 2 ms 7260 KB Output is correct
4 Incorrect 236 ms 26020 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 243 ms 26248 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7260 KB Output is correct
2 Correct 2 ms 7260 KB Output is correct
3 Correct 1 ms 7260 KB Output is correct
4 Correct 3 ms 7260 KB Output is correct
5 Correct 1 ms 5212 KB Output is correct
6 Correct 1 ms 5212 KB Output is correct
7 Incorrect 2 ms 7260 KB Output isn't correct
8 Halted 0 ms 0 KB -