Submission #556172

#	Time	Username	Problem	Language	Result	Execution time	Memory
556172		jesus_coconut	Meetings 2 (JOI21_meetings2)	C++17	100 / 100	2726 ms	26828 KiB

meetings2

#include <bits/stdc++.h>
#define F first
#define S second
#define all(a) begin(a), end(a)
#define pb push_back
#define eb emplace_back


using namespace std;

using ll = long long;

int const N = 1 << 18;


int n;
vector<vector<int>> adj;

int sz[N];
bitset<N> rem;

void dfssz(int ver, int par) {
    sz[ver] = 1;
    for (auto u : adj[ver]) if (u != par && !rem[u]) {
        dfssz(u, ver);
        sz[ver] += sz[u];
    }
}

int getCentroid(int ver, int par, int msz) {
    for (auto u : adj[ver]) if (u != par && !rem[u]) {
        if (2 * sz[u] > msz) return getCentroid(u, ver, msz);
    }
    return ver;
}
int ans[N];
struct SegTree {
    int val[2 * N];

    void upd(int p, int v, int ver, int lx, int rx, bool smx) {
        if (rx - lx == 1) {
            if (smx) val[ver] = max(val[ver], v);
            else val[ver] = v;
            return;
        }
        int mx = (lx + rx) / 2;
        if (p < mx) upd(p, v, ver * 2 + 1, lx, mx, smx);
        else        upd(p, v, ver * 2 + 2, mx, rx, smx);
        val[ver] = max(val[ver * 2 + 1], val[ver * 2 + 2]);
    }

    int query(int l, int r, int ver, int lx, int rx) {
        if (rx <= l || r <= lx) return INT_MIN;
        if (l <= lx && rx <= r) return val[ver];
        int mx = (lx + rx) / 2;
        int a = query(l, r, ver * 2 + 1, lx, mx);
        int b = query(l, r, ver * 2 + 2, mx, rx);
        return max(a, b);
    }

    int query(int l, int r) { return query(l, r, 0, 0, N); }

    void upd(int p, int v, bool smx) { upd(p, v, 0, 0, N, smx); }
};

SegTree mxDist;

int ub;

void dfs(int ver, int par, int dep, bool write) {
    if (write) mxDist.upd(sz[ver], dep, true);
    else {
        ans[sz[ver]] = max(ans[sz[ver]], dep + mxDist.query(sz[ver], ub) + 1);
    }
    for (auto u : adj[ver]) if (u != par && !rem[u]) {
        dfs(u, ver, dep + 1, write);
    }
}

void centroid(int start) {
    dfssz(start, -1);
    int cen = getCentroid(start, -1, sz[start]);
    dfssz(cen, -1);
    ub = sz[cen] + 5;
    for (int i = 0; i < ub; ++i) {
        mxDist.upd(i, 0, false);
    }
    vector<int> tmp;
    for (auto u : adj[cen]) if (!rem[u]) {
        tmp.push_back(u);
        dfs(u, cen, 1, 0);
        dfs(u, cen, 1, 1);
    }
    for (int i = 0; i < ub; ++i) {
        mxDist.upd(i, 0, false);
    }
    reverse(begin(tmp), end(tmp));
    for (auto u : tmp) {
        dfs(u, cen, 1, 0);
        dfs(u, cen, 1, 1);
    }
    rem[cen] = true;
    for (auto u : adj[cen]) {
        if (!rem[u]) centroid(u);
    }
}


void solve() {
    cin >> n;
    adj.resize(n);
    for (int i = 0; i < n - 1; ++i) {
        int a, b;
        cin >> a >> b;
        --a; --b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    centroid(0);
    ans[N-1] = max(ans[N-1], 1);
    for (int i = N - 2; i >= 0; --i) ans[i] = max(ans[i], ans[i+1]);
    for (int i = 1; i <= n; ++i) {
        if (i % 2) cout << 1 << '\n';
        else {
            cout << ans[i/2] << '\n';
        }
    }
}



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


    solve();


    return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 16 / 16
• Subtask 3: 80 / 80