Submission #434346

# Submission time Handle Problem Language Result Execution time Memory
434346 2021-06-21T02:53:55 Z cuom1999 Werewolf (IOI18_werewolf) C++14
15 / 100
4000 ms 166408 KB
#include <bits/stdc++.h>
using namespace std;

struct DSU {
    vector<int> lab;
    DSU(int n) {
        lab.assign(n + 1, -1);
    }

    int merge(int a, int b) {
        if (lab[a] > lab[b]) {
            swap(a, b);
        }
        lab[a] += lab[b];
        lab[b] = a;
        return a;
    }

    int getRoot(int a) {
        while (lab[a] >= 0) a = lab[a];
        return a;
    }
};

struct DSUTree {
    struct Node {
        int tin, tout, weight;
        vector<int> child;
    };

    int n, TIME = 0;
    vector<array<int, 3>> edges;
    vector<int> root, eulerTour;
    vector<vector<int>> par;
    vector<Node> nodes;
    
    DSUTree(int n): n(n) {
        root.resize(n + 1);
        nodes.resize(2 * n);
        par.assign(2 * n, vector<int>(20));
    }

    void addEdge(int u, int v, int c) {
        edges.push_back({c, u, v});
    }

    void construct() {
        sort(edges.begin(), edges.end());
        DSU dsu(n);

        for (int i = 1; i <= n; i++) {
            root[i] = i;
            nodes[i].weight = -1e9;
        }

        int cnt = n;
        for (auto e: edges) {
            int a = dsu.getRoot(e[1]);
            int b = dsu.getRoot(e[2]);
            if (a == b) continue;

            int root1 = root[a], root2 = root[b];
            a = dsu.merge(a, b);
            root[a] = ++cnt;
            nodes[cnt].child.push_back(root1);
            nodes[cnt].child.push_back(root2);
            nodes[cnt].weight = e[0];

            par[root1][0] = cnt;
            par[root2][0] = cnt;
        }

        dfs(2 * n - 1);
        getOrder();

        for (int i = 1; i < 20; i++) {
            for (int j = 1; j <= 2 * n - 1; j++) {
                par[j][i] = par[par[j][i - 1]][i - 1];
            }
        }
    }

    void dfs(int u) {
        nodes[u].tin = ++TIME;
        eulerTour.push_back(u);
        for (auto i: nodes[u].child) {
            dfs(i);
        }
        nodes[u].tout = ++TIME;
        eulerTour.push_back(u);
    }

    vector<int> order;
    void getOrder() {
        vector<int> vs(2 * n + 1);
        for (auto i: eulerTour) {
            if (i <= n && vs[i] == 0) {
                order.push_back(i);
            }
            vs[i] = 1;
        }
    }

    // return the interval that s can reach through edges <= r
    pair<int, int> getInterval(int s, int r) {
        // find farthest parent has weight <= r
        for (int i = 19; i >= 0; i--) {
            int p = par[s][i];
            if (p && nodes[p].weight <= r) {
                s = p;
            }
        }

        // find [l, r] such that tin[s] <= tin[i] <= tout[s]
        int lower = 0, upper = n - 1;
        while (lower < upper) {
            int mid = (lower + upper) / 2;
            if (nodes[s].tin <= nodes[order[mid]].tin) {
                upper = mid;
            }
            else {
                lower = mid + 1;
            }
        }

        int l = lower;

        lower = 0, upper = n - 1;
        while (lower < upper) {
            int mid = (lower + upper + 1) / 2;
            if (nodes[s].tout >= nodes[order[mid]].tin) {
                lower = mid;
            }
            else {
                upper = mid - 1;
            }
        }

        return {l, lower};
    }
};

std::vector<int> check_validity(int n, std::vector<int> x, std::vector<int> y,
                                std::vector<int> S, std::vector<int> E,
                                std::vector<int> L, std::vector<int> R) {
    int m = x.size(), q = S.size();
    DSUTree maxTree(n), minTree(n);
    for (int i = 1; i <= m; i++) {
        int u = x[i - 1], v = y[i - 1];
        u++; v++;
        maxTree.addEdge(u, v, -min(u, v)); // >= l
        minTree.addEdge(u, v, max(u, v)); // <= r
    }

    minTree.construct();
    maxTree.construct();

    vector<int> a = minTree.order;
    vector<int> b = maxTree.order;
    vector<int> pos(n + 1), c(n + 1);

    // for (auto i: a) cout << i << " ";
    // cout << endl;
    // for (auto i: b) cout << i << " ";
    // cout << endl;

    for (int i = 0; i < n; i++) {
        pos[a[i]] = i + 1;
    }
    for (int i = 0; i < n; i++) {
        c[i + 1] = pos[b[i]];
    }

    vector<int> ret;
    for (int i = 0; i < q; i++) {
        int s = S[i], e = E[i], l = L[i], r = R[i];
        // cin >> s >> e >> l >> r;
        s++; e++; l++; r++;
        auto [l1, r1] = minTree.getInterval(e, r);
        auto [l2, r2] = maxTree.getInterval(s, -l);

        // cout << l1 << " " << r1 << " " << l2 << " " << r2 << endl;
        vector<int> vs(n + 1);
        for (int i = l1; i <= r1; i++) {
            vs[a[i]]++;
        }
        int res = 0;
        for (int i = l2; i <= r2; i++) {
            if (vs[b[i]]) res = 1;
        }
        // cout << res << '\n';
        ret.push_back(res);
    }

    return ret;
}

Compilation message

werewolf.cpp: In function 'std::vector<int> check_validity(int, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
werewolf.cpp:179:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  179 |         auto [l1, r1] = minTree.getInterval(e, r);
      |              ^
werewolf.cpp:180:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  180 |         auto [l2, r2] = maxTree.getInterval(s, -l);
      |              ^
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 35 ms 2764 KB Output is correct
11 Correct 27 ms 2764 KB Output is correct
12 Correct 13 ms 2796 KB Output is correct
13 Correct 40 ms 2920 KB Output is correct
14 Correct 36 ms 2892 KB Output is correct
15 Correct 31 ms 2988 KB Output is correct
# Verdict Execution time Memory Grader output
1 Execution timed out 4097 ms 166408 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 35 ms 2764 KB Output is correct
11 Correct 27 ms 2764 KB Output is correct
12 Correct 13 ms 2796 KB Output is correct
13 Correct 40 ms 2920 KB Output is correct
14 Correct 36 ms 2892 KB Output is correct
15 Correct 31 ms 2988 KB Output is correct
16 Execution timed out 4097 ms 166408 KB Time limit exceeded
17 Halted 0 ms 0 KB -