oj.uz

Submission #485580

# Submission time Handle Problem Language Result Execution time Memory
485580 2021-11-08T11:15:03 Z sam571128 Love Polygon (BOI18_polygon) C++17
29 / 100
 246 ms 31180 KB 
#include <bits/stdc++.h>

#define int long long
#define fastio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

using namespace std;

const int N = 1e5+5;
int visited[N], arr[N], sz[N], dp[N][2], col[N], ok[N], dp2[N][2];
vector<int> adj[N];


void dfs(int u, int p, int no = -1){
    visited[u] = 1;
    sz[u] = 1;
    int sum = 0, sum2 = 0;
    for(auto v : adj[u]){
        if(v==p || visited[v] || (arr[u]==no&&v==no)) continue;
        dfs(v,u,no);
        sum += dp[v][0];
        sum2 += dp2[v][0];
        sz[u] += sz[v];
    }

    int mx = 0, mx2 = 0;
    for(auto v : adj[u]){
        if(v==p) continue;
        mx = max(dp[v][1]-dp[v][0],mx);
        mx2 = max(dp2[v][1]-dp2[v][0],mx2);
    }


    dp[u][1] = sum+1;

    if(u!=no) dp2[u][1] = sum2+1;
    else dp2[u][1] = -1e18;

    dp[u][0] = mx+dp[u][1]-1;
    dp2[u][0] = max((int)0,mx2+dp2[u][1]-1);
}

int idx;
map<string,int> m;

int assign(string x){
    if(m.find(x)==m.end()){
        m[x] = idx++;
    }
    return m[x];
}

signed main(){
    fastio
    int n;
    cin >> n;

    for(int i = 0;i < n;i++){
        string a,b;
        cin >> a >> b;
        int x = assign(a);
        int y = assign(b);
        arr[x] = y;
        if(x==y) continue;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    if(n%2){
        cout << -1 << "\n";
        return 0;
    }

    for(int i = 0; i < n; i++){
        if(arr[arr[i]]==i){
            if(adj[arr[i]].size()==2){
                ok[i] = 1;
                visited[arr[i]] = 1;
            }else{
                ok[arr[i]] = 1;
                visited[i] = 1;
            }  
        }
    }

    int ans = 0;
    for(int i = 0; i < n; i++){
        if(arr[i]==i){
            dfs(i,i);
            ans += sz[i]-dp[i][0];
        }
    }

    for(int i = 0; i < n; i++){
        if(!visited[i]){
            if(ok[i]){
                dfs(i,i);
                ans += sz[i]-dp[i][1];
            }else{
                dfs(i,i,arr[i]);
                ans += sz[i]-max(dp[i][0],dp2[i][1]);
            }
        }
    }


    cout << ans << "\n";
}

Subtask #1
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 1 ms 2636 KB Output is correct
4 Incorrect 2 ms 2764 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 1 ms 2636 KB Output is correct
3 Correct 1 ms 2636 KB Output is correct
4 Incorrect 246 ms 30200 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 235 ms 22384 KB Output is correct
2 Correct 230 ms 23712 KB Output is correct
3 Correct 167 ms 18656 KB Output is correct
4 Correct 204 ms 16964 KB Output is correct
5 Correct 240 ms 31180 KB Output is correct
6 Correct 237 ms 21732 KB Output is correct
7 Correct 226 ms 22224 KB Output is correct
8 Correct 193 ms 21100 KB Output is correct
9 Correct 235 ms 21828 KB Output is correct
10 Correct 146 ms 21848 KB Output is correct
11 Correct 2 ms 2636 KB Output is correct
12 Correct 2 ms 2672 KB Output is correct
13 Correct 2 ms 2672 KB Output is correct
14 Correct 1 ms 2636 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 1 ms 2636 KB Output is correct
4 Incorrect 2 ms 2764 KB Output isn't correct
5 Halted 0 ms 0 KB -