oj.uz

Submission #442536

# Submission time Handle Problem Language Result Execution time Memory
442536 2021-07-08T06:41:48 Z abc864197532 Love Polygon (BOI18_polygon) C++17
54 / 100
 324 ms 36336 KB 
#include <bits/stdc++.h>
using namespace std;
#define lli long long int
#define X first
#define Y second
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define pii pair<int, int>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define test(args...) abc("[" + string(#args) + "]", args)
void abc() {cerr << endl;}
template <typename T, typename ...U> void abc(T a, U ...b) {
    cerr << a << ' ', abc(b...);
}
template <typename T> void printv(T l, T r) {
    while (l != r) cerr << *l << " \n"[++l == r];
}
const int mod = 1e9 + 7, N = 200000;

int dsu[N];

int Find(int x) {
    if (x == dsu[x]) return x;
    return dsu[x] = Find(dsu[x]);
}

bool Union(int u, int v) {
    u = Find(u), v = Find(v);
    if (u == v) return false;
    dsu[u] = v;
    return true;
}

int main () {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, _id = 0;
    cin >> n;
    if (n & 1) return cout << -1 << endl, 0;
    map <string, int> m1;
    auto get = [&](string s) {
        if (m1.count(s)) return m1[s];
        return m1[s] = _id++;
    };
    for (int i = 0; i < n; ++i) dsu[i] = i;
    vector <vector <int>> adj(n);
    vector <int> pt(n);
    string s, t;
    vector <pii> oth;
    for (int i = 0; i < n; ++i) {
        cin >> s >> t;
        int u = get(s), v = get(t);
        pt[u] = v;
        if (Union(u, v)) adj[v].pb(u), adj[u].pb(v);
        else oth.eb(v, u);
    }
    vector <int> cur;
    vector <vector <int>> dp1(n, vector <int>(2, 0));
    vector <vector <int>> dp2(n, vector <int>(2, 0));
    // 0 not choose, 1 choose
    vector <bool> vis(n, false);
    int cnt = 0;
    function<void(int, int, int)> dfs = [&](int v, int pa, int out) {
        cnt++;
        for (int u : adj[v]) if (u != pa) {
            dfs(u, v, out);
            dp1[v][0] += max(dp1[u][0], dp1[u][1]);
            dp2[v][0] += max(dp2[u][0], dp2[u][1]);
        }
        for (int u : adj[v]) if (u != pa) {
            dp1[v][1] = max(dp1[v][1], dp1[v][0] - max(dp1[u][0], dp1[u][1]) + dp1[u][0] + 1);
            if (u != out) dp2[v][1] = max(dp2[v][1], dp2[v][0] - max(dp2[u][0], dp2[u][1]) + dp2[u][0] + 1);
        }
    };
    int ans = n;
    for (pii A : oth) {
        cnt = 0;
        dfs(A.X, -1, A.Y);
        if (A.X != A.Y) ans -= max({dp1[A.X][0], dp1[A.X][1], dp2[A.X][0] + (pt[A.X] == A.Y && pt[A.Y] == A.X ? 2 : 1)});
        else ans -= max(dp1[A.X][0], dp1[A.X][1]);
    }
    cout << ans << endl;
}

Subtask #1
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Incorrect 1 ms 204 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 324 ms 34880 KB Output is correct
5 Correct 279 ms 25408 KB Output is correct
6 Correct 310 ms 36336 KB Output is correct
7 Correct 0 ms 204 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 313 ms 25320 KB Output is correct
2 Correct 301 ms 27780 KB Output is correct
3 Correct 188 ms 23020 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 309 ms 35396 KB Output is correct
6 Correct 283 ms 25412 KB Output is correct
7 Correct 281 ms 25376 KB Output is correct
8 Correct 282 ms 24992 KB Output is correct
9 Correct 254 ms 25760 KB Output is correct
10 Correct 177 ms 25684 KB Output is correct
11 Correct 0 ms 204 KB Output is correct
12 Correct 1 ms 204 KB Output is correct
13 Correct 0 ms 204 KB Output is correct
14 Correct 0 ms 204 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Incorrect 1 ms 204 KB Output isn't correct
10 Halted 0 ms 0 KB -