oj.uz

Submission #642492

# Submission time Handle Problem Language Result Execution time Memory
642492 2022-09-19T15:17:12 Z FedShat Usmjeri (COCI17_usmjeri) C++17
28 / 140
 190 ms 32632 KB 
#include <bits/stdc++.h>

using namespace std;
using ll = long long;
constexpr int INF = numeric_limits<int>::max() / 2;
constexpr ll INFLL = numeric_limits<ll>::max() / 2;

template<class T>
istream &operator>>(istream &is, vector<T> &a) {
    for (auto &i : a) {
        is >> i;
    }
    return is;
}

constexpr int mod = 1e9 + 7;

struct BinaryJumps {
    static constexpr int k = 20;
    vector<vector<int>> up;
    vector<int> depth;

    BinaryJumps() {
    }

    BinaryJumps(int n) {
        up.resize(k, vector<int>(n));
        depth.resize(n);
    }

    void add_leaf(int v, int p) {
        up[0][v] = p;
        depth[v] = depth[p] + 1;
        for (int i = 1; i < k; ++i) {
            up[i][v] = up[i - 1][up[i - 1][v]];
        }
    }

    int up_k(int v, int d) {
        for (int i = k - 1; i >= 0; --i) {
            if (d >= (1 << i)) {
                v = up[i][v];
                d -= (1 << i);
            }
        }
        return v;
    }

    int LCA(int u, int v) {
        if (depth[u] < depth[v]) {
            swap(u, v);
        }
        u = up_k(u, depth[u] - depth[v]);
        for (int i = k - 1; i >= 0; --i) {
            if (up[i][u] != up[i][v]) {
                u = up[i][u];
                v = up[i][v];
            }
        }
        if (u == v) {
            return u;
        }
        return up[0][u];
    }
};

vector<vector<int>> g;
vector<int> par;
BinaryJumps t;

void dfs(int v, int p) {
    par[v] = p;
    for (auto u : g[v]) {
        if (u != p) {
            t.add_leaf(u, v);
            dfs(u, v);
        }
    }
}

vector<vector<pair<int, int>>> gr;
vector<int> color;
bool ok = 1;

void dfs2(int v) {
    for (auto [u, c] : gr[v]) {
        int cur = (c ? color[v] : color[v] ^ 1);
        if (color[u] == -1) {
            color[u] = cur;
            dfs2(u);
        } else {
            if (color[u] != cur) {
                ok = 0;
            }
        }
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
#ifdef __APPLE__
    freopen("input.txt", "r", stdin);
#endif
    int n, q;
    cin >> n >> q;
    g.resize(n);
    for (int i = 0; i < n - 1; ++i) {
        int u, v;
        cin >> u >> v;
        --u;
        --v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    vector<pair<int, int>> v;
    for (int i = 0; i < q; ++i) {
        int a, b;
        cin >> a >> b;
        v.push_back({a, 1});
        v.push_back({b, -1});
    }
    sort(v.begin(), v.end(), [](pair<int, int> a, pair<int, int> b) {
        return a.first < b.first || (a.first == b.first && a.second > b.second);
    });
    int sum = 0, balance = 0, l = 0, r = 0, ans = 1;
    for (int i = 0; i < (int) v.size(); ++i) {
        balance += v[i].second;
        if (i != 0 && balance == 0) {
            sum += v[r].first - v[l].first;
            l = r + 1;
            ++r;
            ans = (ans * 2ll) % mod;
        } else {
            ++r;
        }
    }
    for (int i = 0; i < n - 1 - sum; ++i) {
        ans = (ans * 2ll) % mod;
    }
    cout << ans << "\n";
    // t = BinaryJumps(n);
    // par.resize(n);
    // dfs(0, -1);
    // gr.resize(n);
    // auto add_edge = [&](int u, int v, int c) {
    //     gr[u].push_back({v, c});
    //     gr[v].push_back({u, c});
    // };
    // while (q--) {
    //     int u, v;
    //     cin >> u >> v;
    //     --u;
    //     --v;
    //     if (t.depth[u] < t.depth[v]) {
    //         swap(u, v);
    //     }
    //     int l = t.LCA(u, v);
    //     if (l == v) {// verticals
    //         int curu = u;
    //         while (par[curu] != l) {
    //             add_edge(curu, par[curu], 1);// equal
    //             curu = par[curu];
    //         }
    //     } else {
    //         int curu = u;
    //         while (par[curu] != l) {
    //             add_edge(curu, par[curu], 1);// equal
    //             curu = par[curu];
    //         }
    //         int curv = u;
    //         while (par[curv] != l) {
    //             add_edge(curv, par[curv], 1);// equal
    //             curv = par[curv];
    //         }
    //         add_edge(curu, curv, 0);
    //     }
    // }
    // int ans = 1;
    // color.resize(n, -1);
    // for (int i = 1; i < n; ++i) {
    //     if (color[i] == -1) {
    //         color[i] = 0;
    //         dfs2(i);
    //         ans = (ans * 2ll) % mod;
    //     }
    // }
    // if (!ok) {
    //     cout << "0\n";
    // } else {
    //     cout << ans << "\n";
    // }
}

Subtask #1
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 85 ms 12660 KB Output is correct

Subtask #2
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 161 ms 31916 KB Output is correct

Subtask #3
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 724 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 724 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #7
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 190 ms 32472 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #8
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 175 ms 32480 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #9
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 181 ms 32560 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #10
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 188 ms 32632 KB Output isn't correct
2 Halted 0 ms 0 KB -