oj.uz

Submission #540277

# Submission time Handle Problem Language Result Execution time Memory
540277 2022-03-19T19:49:50 Z surgutti Capital City (JOI20_capital_city) C++17
0 / 100
 3000 ms 48844 KB 
#include <bits/stdc++.h>

using namespace std;

const int N = 200'007;

int n, k;
vector<int> adj[N];
int c[N];

vector<int> col[N];
int vis[N], sz[N], par[N], done[N], tim;
vector<int> cur[N];

void prepare(int u, int f) {
    sz[u] = 1;
    cur[c[u]].push_back(u);
    for (int v : adj[u]) if (!vis[v] && v != f) {
        prepare(v, u);
        sz[u] += sz[v];
        par[v] = u;
    }
}

int find_centroid(int u, int f, int all) {
    for (int v : adj[u]) if (!vis[v] && v != f) {
        if (sz[v] >= all / 2) {
            return find_centroid(v, u, all);
        }
    }
    return u;
}

void clear(int u, int f) {
    cur[c[u]].clear();
    for (int v : adj[u]) if (!vis[v] && v != f) {
        clear(v, u);
    }
}

int ans = N;

void solve(int u) {

    prepare(u, u);

    int centroid = find_centroid(u, u, sz[u]);

    clear(u, u);

    prepare(centroid, centroid);

    queue<int> q;
    q.push(c[centroid]);

    ++tim;

    done[c[centroid]] = tim;

    int now = 0;
    while (q.size()) {
        int v = q.front(); q.pop();
        now++;

        if (cur[v].size() != col[v].size()) {
            now = N;
            break;
        }

        for (int w : cur[v]) if (w != centroid) {
            w = par[w];
            if (done[c[w]] != tim) {
                done[c[w]] = tim;
                q.push(c[w]);
            }
        }
    }
   
    ans = min(ans, now - 1);

    clear(u, u);

    vis[u] = true;

    for (int v : adj[u]) if (!vis[v]) {
        solve(v);
    }
}

int main() {
    ios::sync_with_stdio(false), cin.tie(nullptr);

    cin >> n >> k;
    for (int i = 0; i < n - 1; i++) {
        int u, v; cin >> u >> v; u--, v--;

        adj[u].push_back(v);
        adj[v].push_back(u);
    }

    for (int i = 0; i < n; i++) {
        cin >> c[i]; c[i]--;
        col[c[i]].push_back(i);
    }

    solve(0);

    cout << ans << '\n';
}

Subtask #1
0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 8 ms 14564 KB Output is correct
3 Correct 8 ms 14436 KB Output is correct
4 Correct 8 ms 14436 KB Output is correct
5 Correct 7 ms 14420 KB Output is correct
6 Correct 8 ms 14436 KB Output is correct
7 Incorrect 9 ms 14456 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 8 ms 14564 KB Output is correct
3 Correct 8 ms 14436 KB Output is correct
4 Correct 8 ms 14436 KB Output is correct
5 Correct 7 ms 14420 KB Output is correct
6 Correct 8 ms 14436 KB Output is correct
7 Incorrect 9 ms 14456 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Execution timed out 3051 ms 48844 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 59.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 8 ms 14564 KB Output is correct
3 Correct 8 ms 14436 KB Output is correct
4 Correct 8 ms 14436 KB Output is correct
5 Correct 7 ms 14420 KB Output is correct
6 Correct 8 ms 14436 KB Output is correct
7 Incorrect 9 ms 14456 KB Output isn't correct
8 Halted 0 ms 0 KB -