Submission #1287419

#	Time	Username	Problem	Language	Result	Execution time	Memory
1287419		red_souls	Grapevine (NOI22_grapevine)	C++17	53 / 100	1110 ms	242948 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define task "GRAPEVINE"
using namespace std;

const int N = 1e5 + 16;
const ll INF = 1e18;
int n, q, u, v;
ll w;
vector < pair <int, ll> > adj[N];

namespace sub6 {

    int h[N], up[N][26], timeDfs, in[N], out[N];
    ll d[N], val[N];

    void dfs(int k) {
        timeDfs++;
        in[k] = timeDfs;
        for (auto v : adj[k]) {
            if (v.first == up[k][0]) {
                continue;
            }
            d[v.first] = d[k] + v.second;
            val[v.first] = v.second;
            h[v.first] = h[k] + 1;
            up[v.first][0] = k;
            for (int i = 1; i <= 20; i++) {
                up[v.first][i] = up[up[v.first][i - 1]][i - 1];
            }
            dfs(v.first);
        }
        out[k] = timeDfs;
    }

    int lca(int u, int v) {
        if (h[u] != h[v]) {
            if (h[u] < h[v]) {
                swap(u, v);
            }
            int k = h[u] - h[v];
            for (int i = 0; (1 << i) <= k; i++) {
                if (k >> i & 1) {
                    u = up[u][i];
                }
            }
        }
        if (u == v) {
            return u;
        }
        int k = __lg(h[u]);
        for (int i = k; i >= 0; i--) {
            if (up[u][i] != up[v][i]) {
                u = up[u][i];
                v = up[v][i];
            }
        }
        return up[u][0];
    }

    bool checkSubtree(int root, int k) {
        return in[root] <= in[k] && out[k] <= out[root];
    }

    bool cmp(int a, int b) {
        return in[a] < in[b];
    }

    int sz[N], parCd[N];
    bool visited[N];

    void countChild(int k, int p) {
        sz[k] = 1;
        for (auto v : adj[k]) {
            if (v.first == p || visited[v.first]) {
                continue;
            }
            countChild(v.first, k);
            sz[k] += sz[v.first];
        }
    }

    int findCentroid(int k, int p, int treeSz) {
        for (auto v : adj[k]) {
            if (v.first == p || visited[v.first]) {
                continue;
            }
            if (sz[v.first] > (treeSz >> 1)) {
                return findCentroid(v.first, k, treeSz);
            }
        }
        return k;
    }

    int cd(int k) {
        countChild(k, k);
        int centroid = findCentroid(k, k, sz[k]);
        visited[centroid] = true;

        for (auto v : adj[centroid]) {
            if (!visited[v.first]) {
                parCd[cd(v.first)] = centroid;
            }
        }
        return centroid;
    }

    struct node {
        ll d = INF, answer = INF;
        int state = 0;
        ll lazy = 0;

        node operator + (const node &other) const {
            node ans;
            if (answer < other.answer) {
                ans.d = d;
                ans.answer = answer;
                ans.state = state;
            }
            else {
                ans.d = other.d;
                ans.answer = other.answer;
                ans.state = other.state;
            }
            return ans;
        }
    };

    struct IT {
        int n, root;
        vector <int> lst;
        vector <node> segmentTree;

        void build(int k, int l, int r) {
            if (l == r) {
                segmentTree[k].d = d[lst[l - 1]] + d[root] - 2 * d[lca(lst[l - 1], root)];
                return;
            }
            int mid = l + r >> 1;
            build(k << 1, l, mid);
            build(k << 1 | 1, mid + 1, r);
        }

        void down(int k) {
            ll t = segmentTree[k].lazy;
            if (t == 0) {
                return;
            }

            segmentTree[k << 1].d += t;
            segmentTree[k << 1].answer += t;
            segmentTree[k << 1].answer = min(segmentTree[k << 1].answer, INF);
            segmentTree[k << 1].lazy += t;

            segmentTree[k << 1 | 1].d += t;
            segmentTree[k << 1 | 1].answer += t;
            segmentTree[k << 1 | 1].answer = min(segmentTree[k << 1 | 1].answer, INF);
            segmentTree[k << 1 | 1].lazy += t;

            segmentTree[k].lazy = 0;
        }

        void updateRange(int k, int l, int r, int x, int y, ll w) {
            if (l > y || x > r) {
                return;
            }
            if (l >= x && r <= y) {
                segmentTree[k].d += w;
                segmentTree[k].answer += w;
                segmentTree[k].answer = min(segmentTree[k].answer, INF);
                segmentTree[k].lazy += w;
                return;
            }
            int mid = l + r >> 1;
            down(k);
            updateRange(k << 1, l, mid, x, y, w);
            updateRange(k << 1 | 1, mid + 1, r, x, y, w);
            segmentTree[k] = segmentTree[k << 1] + segmentTree[k << 1 | 1];
        }

        void updatePoint(int k, int l, int r, int x) {
            if (l > x || x > r) {
                return;
            }
            if (l == r) {
                segmentTree[k].state ^= 1;
                if (segmentTree[k].state) {
                    segmentTree[k].answer = segmentTree[k].d;
                }
                else {
                    segmentTree[k].answer = INF;
                }
                return;
            }
            int mid = l + r >> 1;
            down(k);
            updatePoint(k << 1, l, mid, x);
            updatePoint(k << 1 | 1, mid + 1, r, x);
            segmentTree[k] = segmentTree[k << 1] + segmentTree[k << 1 | 1];
        }

        ll get(int k, int l, int r, int x) {
            if (l == r) {
                return segmentTree[k].d;
            }
            int mid = l + r >> 1;
            down(k);
            if (x <= mid) {
                return get(k << 1, l, mid, x);
            }
            return get(k << 1 | 1, mid + 1, r, x);
        }
    };

    IT tree[N];

    int lowerBound(vector <int> &lst, int pos) {
        int l = 0, r = lst.size() - 1, mid, res = lst.size();
        while (l <= r) {
            mid = l + r >> 1;
            if (in[lst[mid]] >= pos) {
                r = mid - 1;
                res = mid;
            }
            else {
                l = mid + 1;
            }
        }
        res++;
        return res;
    }

    int upperBound(vector <int> &lst, int pos) {
        int l = 0, r = lst.size() - 1, mid, res = lst.size();
        while (l <= r) {
            mid = l + r >> 1;
            if (in[lst[mid]] > pos) {
                r = mid - 1;
                res = mid;
            }
            else {
                l = mid + 1;
            }
        }
        res++;
        return res;
    }

    ll query(int u) {
        ll ans = INF;
        int cur = u;
        while (cur <= n) {
            int p = lowerBound(tree[cur].lst, in[u]);
            ans = min(ans, tree[cur].get(1, 1, tree[cur].n, p) + tree[cur].segmentTree[1].answer);
            cur = parCd[cur];
        }
        if (ans == INF) {
            ans = -1;
        }
        return ans;
    }

    void change(int u) {
        int cur = u;
        while (cur <= n) {
            int p = lowerBound(tree[cur].lst, in[u]);
            tree[cur].updatePoint(1, 1, tree[cur].n, p);
            cur = parCd[cur];
        }
    }

    void path(int u, ll w) {
        int cur = u;
        while (cur <= n) {
            int L = lowerBound(tree[cur].lst, in[u]);
            int R = upperBound(tree[cur].lst, out[u]);
            R--;
            if (L <= R && R <= tree[cur].n) {
                if (checkSubtree(u, cur)) {
                    if (L - 1 >= 1) {
                        tree[cur].updateRange(1, 1, tree[cur].n, 1, L - 1, w);
                    }
                    if (R + 1 <= tree[cur].n) {
                        tree[cur].updateRange(1, 1, tree[cur].n, R + 1, tree[cur].n, w);
                    }
                }
                else {
                    tree[cur].updateRange(1, 1, tree[cur].n, L, R, w);
                }
            }
            cur = parCd[cur];
        }
    }

    void solve() {
        dfs(1);
        parCd[cd(1)] = n + 1;
        for (int i = 1; i <= n; i++) {
            u = i;
            while (u) {
                tree[u].lst.push_back(i);
                u = parCd[u];
            }
        }
        for (int i = 1; i <= n; i++) {
            sort(tree[i].lst.begin(), tree[i].lst.end(), cmp);
        }
        for (int i = 1; i <= n; i++) {
            tree[i].n = tree[i].lst.size();
            tree[i].root = i;
            node defVal;
            tree[i].segmentTree.resize((tree[i].n + 1) << 2, defVal);
            tree[i].build(1, 1, tree[i].n);
        }
        while (q--) {
            int type, u;
            cin >> type >> u;
            if (type == 1) {
                cout << query(u) << "\n";
            }
            else if (type == 2) {
                change(u);
            }
            else {
                cin >> v >> w;
                int p = h[u] < h[v] ? v : u;
                path(p, w - val[p]);
                val[p] = w;
            }
        }
    }
}

int main() {
    ios_base :: sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }

    cin >> n >> q;
    for (int i = 1; i < n; i++) {
        cin >> u >> v >> w;
        adj[u].push_back({v, w});
        adj[v].push_back({u, w});
    }
    sub6 :: solve();

    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:340:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  340 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:341:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  341 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 14 / 14
• Subtask 3: 15 / 15
• Subtask 4: 0 / 15
• Subtask 5: 18 / 18
• Subtask 6: 0 / 32