Submission #963027

#	Time	Username	Problem	Language	Result	Execution time	Memory
963027		Mtaylor	Tourism (JOI23_tourism)	C++17	100 / 100	1222 ms	53224 KiB

tourism

// Mtaylor
#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define fi first
#define se second
#define mp make_pair
#define endl '\n';
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
void dbg_out() { cerr << endl; }
template <typename Head, typename... Tail>
void dbg_out(Head H, Tail... T) {
    cerr << ' ' << H;
    dbg_out(T...);
}
#define dbg(...) cerr << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
typedef long long ll;
const int N = 3e5 + 5;
template <typename T>
class FenwickTree {
   public:
    vector<T> tree;
    int n;
    void init(int n) {
        tree.assign(n + 2, 0);
        this->n = n;
    }
    T mrg(T &x, T &y) { return x + y; }

    void upd(int x, T v) {
        for (; x <= n; x += (x) & (-x)) {
            tree[x] = mrg(tree[x], v);
        }
    }
    T getprefix(int x) {
        if (x <= 0) return 0;
        T rs = 0;
        for (; x; x -= (x) & (-x)) {
            rs = mrg(rs, tree[x]);
        }
        return rs;
    }
    T getrange(int l, int r) { return getprefix(r) - getprefix(l - 1); }
};
FenwickTree<ll> ft;
int nxt[N];
int val[N];
set<int> intervals;

void updateAns(int l, int r, int x) {
    set<int>::iterator it;
    it = intervals.lower_bound(l);
    if (it != intervals.begin()) it--;
    vector<int> to_rem;
    vector<int> to_add;
    while (it != intervals.end()) {
        int a = *it;
        int b = nxt[a];
        if (a > r) break;
        if (a < l && b < l) {
            it++;
            continue;
        }
        if (a < l) {
            ft.upd(val[a], -(b - a + 1));
            nxt[a] = l - 1;
            ft.upd(val[a], (nxt[a] - a + 1));
        } else {
            ft.upd(val[a], -(b - a + 1));
            to_rem.pb(a);
        }
        if (b > r) {
            to_add.pb(r + 1);
            val[r+1]=val[a];
            ft.upd(val[a], b - r);
            nxt[r + 1] = b;
        }
        it++;
    }
    nxt[l] = r;
    val[l] = x;
    ft.upd(x, r - l + 1);
    for (auto &u : to_rem) {
        assert(intervals.count(u));
        intervals.erase(u);
    }
    for (auto &u : to_add) {
        intervals.insert(u);
    }
    intervals.insert(l);
}

const int E = 1e6 + 5;

#define neig(u, v, e, g) for (int e = g.head[u], v; ~e && ((v = g.to[e]), 1); e = g.nxt[e])

class ADJ {
   public:
    int head[E], to[E], nxt[E], n, edgcnt = 0;
    ll cst[E];

    void addEdge(int a, int b, int c = 0) {
        nxt[edgcnt] = head[a];
        head[a] = edgcnt;
        to[edgcnt] = b;
        cst[edgcnt] = c;
        edgcnt++;
    }

    void addBiEdge(int a, int b, int c = 0) {
        addEdge(a, b, c);
        addEdge(b, a, c);
    }
    void init(int _n) {
        n = _n;
        memset(head, -1, n * sizeof(head[0]));
        edgcnt = 0;
    }
} adj;

class HLD {
   public:
    vector<int> par, sze, dpth, ndToIdx, chHead, heavyChld, idxToNd;
    int n, curPos;
    HLD() {}
    void run(ADJ &adj) {
        n = adj.n;
        curPos = 0;
        par.assign(n, -1);
        sze.assign(n, 0);
        dpth.assign(n, 0);
        ndToIdx.assign(n, 0);
        chHead.assign(n, 0);
        heavyChld.assign(n, 0);
        idxToNd.assign(n, 0);
        calcsz(0, adj);
        HLD_util(0, adj);
    }
    void calcsz(int u, ADJ &adj) {
        heavyChld[u] = -1;
        sze[u] = 1;
        int mx = 0, mxv;
        neig(u, v, e, adj) {
            if (par[u] == v) continue;
            par[v] = u;
            dpth[v] = dpth[u] + 1;
            calcsz(v, adj);
            if (sze[v] > mx) {
                mx = sze[v];
                mxv = v;
            }
            sze[u] += sze[v];
        }
        if (mx * 2 > sze[u]) {
            heavyChld[u] = mxv;
        }
    }

    void HLD_util(int u, ADJ &adj, int c = 0) {
        if (u == -1) return;
        idxToNd[curPos] = u;
        ndToIdx[u] = curPos++;
        chHead[u] = c;
        HLD_util(heavyChld[u], adj, c);
        neig(u, v, e, adj) {
            if (v == par[u]) continue;
            if (v == heavyChld[u]) continue;
            HLD_util(v, adj, v);
        }
    }
    int lca(int u, int v) {
        while (chHead[u] != chHead[v]) {
            if (dpth[chHead[v]] > dpth[chHead[u]]) swap(u, v);
            u = par[chHead[u]];
        }
        if (dpth[u] > dpth[v]) swap(u, v);
        return u;
    }
    int getDist(int u, int v) {
        int l = lca(u, v);
        return dpth[u] + dpth[v] - 2 * dpth[l];
    }
    void update(int u, int v, int x) {
        while (chHead[u] != chHead[v]) {
            if (dpth[chHead[v]] > dpth[chHead[u]]) {
                swap(u, v);
            }
            updateAns(ndToIdx[chHead[u]], ndToIdx[u], x);
            u = par[chHead[u]];
        }
        if (dpth[u] > dpth[v]) {
            swap(u, v);
        }
        updateAns(ndToIdx[u], ndToIdx[v], x);
    }
} hld;

int n, m, q;
int c[N];
vector<int> qu[N];
int l[N], r[N];
ll ans[N];
void test_case() {
    cin >> n >> m >> q;
    adj.init(n);
    ft.init(m + 2);
    for (int i = 0; i < n - 1; i++) {
        int u, v;
        cin >> u >> v;
        --u, --v;
        adj.addBiEdge(u, v);
    }

    hld.run(adj);
    for (int i = 1; i <= m; i++) {
        cin >> c[i];
        --c[i];
    }
    for (int i = 0; i < q; i++) {
        cin >> l[i] >> r[i];
        qu[r[i]].pb(i);
    }
    for (int i = 1; i <= m; i++) {
        if (i >= 2) {
            hld.update(c[i - 1], c[i], i - 1);
        }
        hld.update(c[i], c[i], i);
        for (auto &id : qu[i]) {
            ans[id] = ft.getrange(l[id], m + 2);
        }
    }
    for (int i = 0; i < q; i++) {
        cout << ans[i] << "\n";
    }
}

int main() {
    // freopen("input.txt", "r", stdin);
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int T = 1;
    while (T--) {
        test_case();
    }
    return 0;
}

Compilation message (stderr)

tourism.cpp: In member function 'void HLD::calcsz(int, ADJ&)':
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp: In function 'void test_case()':
tourism.cpp:158:26: warning: 'mxv' may be used uninitialized in this function [-Wmaybe-uninitialized]
  158 |             heavyChld[u] = mxv;
tourism.cpp:145:21: note: 'mxv' was declared here
  145 |         int mx = 0, mxv;
      |                     ^~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 7 / 7
• Subtask 4: 18 / 18
• Subtask 5: 24 / 24
• Subtask 6: 41 / 41