oj.uz

Submission #1096672

# Submission time Handle Problem Language Result Execution time Memory
1096672 2024-10-05T01:25:24 Z snowmel Valley (BOI19_valley) C++17
59 / 100
 73 ms 23712 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int N, S, Q, H, C;
vector<pair<int,int>> QRS;
vector<tuple<int,int,ll>> edges;
vector<int> villages;
namespace sub12 {
vector<vector<int>> adj;
vector<int> is_village;
bool check() {
    return 1ll * N * Q <= int(1e6);
}
array<ll,3> dfs(int u, int p = -1) {
    array<ll,3> res;
    res[0] = res[1] = 0;
    res[2] = 1e18;
    if(u == H) res[0] = 1;
    if(is_village[u]) {
        res[1] = 1;
        res[2] = 0;
    }
    for(auto&& eid : adj[u]) {
        auto [ut, vt, w] = edges[eid];
        auto v = (ut != u ? ut : vt);
        if(v == p || w == -1) continue;
        auto t = dfs(v, u);
        res[0] |= t[0];
        res[1] |= t[1];
        if(t[1]) res[2] = min(res[2], t[2] + w);
    }
    return res;
}
void solve() {
    adj.assign(N, vector<int>());
    is_village.assign(N, 0);
    for(int i = 0; auto&& [x, y, z] : edges) {
        adj[x].emplace_back(i);
        adj[y].emplace_back(i);
        ++i;
    }
    for(auto&& v : villages) is_village[v] = 1;
    for(auto&& [x, y] : QRS) {
        auto t = get<2>(edges[x]);
        get<2>(edges[x]) = -1;
        auto tt = dfs(y);
        get<2>(edges[x]) = t;
        if(tt[0]) {
            cout << "escaped\n";
        } else if(tt[1]) {
            cout << tt[2] << "\n";
        } else {
            cout << "oo\n";
        }
    }
}
};
template<typename Monoid>
struct Sparse_Table {
    using MX = Monoid;
    using X = typename MX::value_type;
    int n, log;
    vector<vector<X>> dat;
    Sparse_Table() {}
    template<typename F>
    void build(int _n, F f) {
        n = _n, log = 0;
        while((1 << log) < n) ++log;
        dat.assign(log, vector<X>());
        dat[0].resize(n);
        for(int i = 0; i < n; ++i) dat[0][i] = f(i);
        for(int i = 1; i < log; ++i) {
            dat[i].resize(dat[i - 1].size() - (1 << i - 1));
            for(int j = 0; j < dat[i].size(); ++j) dat[i][j] = MX::op(dat[i - 1][j], dat[i - 1][j + (1 << i - 1)]);
        }
    }
    X prod(int l, int r) {
        assert(0 <= l && l <= r && r <= n);
        if(l == r) return MX::unit();
        if(l + 1 == r) return dat[0][l];
        int k = (31 - __builtin_clz(r - l - 1));
        return MX::op(dat[k][l], dat[k][r - (1 << k)]);
    }
};
template<typename Monoid>
struct SegTree {
    using MX = Monoid;
    using X = typename Monoid::X;
    int n, log, size;
    vector<X> dat;
    SegTree() {}
    template<typename F>
    void build(int _n, F f) {
        n = _n, log = 0;
        while((1 << log) < n) ++log;
        size = 1 << log;
        dat.assign(size << 1, MX::unit());
        for(int i = 0; i < n; ++i) dat[i] = f(i);
        for(int i = size - 1; i >= 1; --i) update(i);
    }
    void set(int k, const X& x) {
        assert(0 <= k && k < n);
        dat[k += size] = x;
        while(k >>= 1) update(k);
    }
    X prod(int l, int r) {
        assert(0 <= l && l <= r && r <= n);
        l += size, r += size;
        X vl = MX::unit(), vr = MX::unit();
        while(l < r) {
            if(l & 1) vl = MX::op(vl, dat[l++]);
            if(r & 1) vr = MX::op(dat[--r], vr);
            l >>= 1, r >>= 1;
        }
        return MX::op(vl, vr);
    }
    void update(int k) { dat[k] = MX::op(dat[k << 1], dat[k << 1 | 1]); }
};
struct Monoid_1 {
    using X = int;
    using value_type = X;
    static constexpr X op(const X& x, const X& y) noexcept { return x | y; }
    static constexpr X unit() noexcept { return 0; }
};
struct Monoid_2 {
    using X = ll;
    using value_type = X;
    static constexpr X op(const X& x, const X& y) noexcept { return min(x, y); }
    static constexpr X unit() noexcept { return 1e18; }
};
namespace sub3 {
bool check() {
    return S == N;
}
vector<vector<int>> adj;
vector<int> LID, RID, parent, V, head;
vector<ll> depth;
void dfs1(int u) {
    auto& sz = RID;
    sz[u] = 1;
    int mx = 0;
    for(auto& eid : adj[u]) {
        auto&& [ut, vt, w] = edges[eid];
        int v = (u != ut ? ut : vt);
        if(v == parent[u]) continue;
        parent[v] = u;
        depth[v] = depth[u] + w;
        dfs1(v);
        sz[u] += sz[v];
        if(sz[v] > mx) {
            mx = sz[v];
            swap(eid, adj[u][0]);
        }
    }
}
void dfs2(int u, int& times) {
    LID[u] = times++;
    RID[u] += LID[u];
    V[LID[u]] = u;
    bool heavy = true;
    for(auto&& eid : adj[u]) {
        auto&& [ut, vt, w] = edges[eid];
        int v = (u != ut ? ut : vt);
        if(v == parent[u]) continue;
        head[v] = (heavy ? head[u] : v);
        heavy = false;
        dfs2(v, times);
    }
}
int ELID(int u) { return (LID[u] << 1) - depth[u]; }
int ERID(int u) { return (RID[u] << 1) - depth[u] - 1; }
int LCA(int u, int v) {
    for(int i = 25; i--; ) {
        if(LID[u] > LID[v]) swap(u, v);
        if(head[u] == head[v]) return u;
        v = parent[head[v]];
    }
    assert(false);
}
vector<pair<int,int>> get_path_decomposition(int u, int v, bool edge = 0) {
    vector<pair<int,int>> up, down;
    while(true) {
        if(head[u] == head[v]) break;
        if(LID[u] < LID[v]) {
            down.emplace_back(LID[head[v]], LID[v]);
            v = parent[head[v]];
        } else {
            up.emplace_back(LID[u], LID[head[u]]);
            u = parent[head[u]];
        }
    }
    if(LID[u] < LID[v]) down.emplace_back(LID[u] + edge, LID[v]);
    else if(LID[v] + edge <= LID[u]) up.emplace_back(LID[u], LID[v] + edge);
    up.insert(up.end(), down.rbegin(), down.rend());
    return up;
}
void solve() {
    adj.assign(N, vector<int>());
    LID.resize(N);
    RID.resize(N);
    parent.resize(N);
    V.resize(N);
    head.resize(N);
    depth.resize(N);
    for(int i = 0; auto&& [x, y, z] : edges) {
        adj[x].emplace_back(i);
        adj[y].emplace_back(i);
        ++i;
    }
    parent[0] = -1;
    dfs1(0);
    int times = 0;
    head[0] = 0;
    dfs2(0, times);
    Sparse_Table<Monoid_2> LCA_TABLE;
    auto lca = [&](int u, int v) {
        static bool is_built = false;
        if(is_built == false) {
            is_built = true;
            vector<int> dat(N << 1);
            for(int i = 0; i < N; ++i) {
                int x = ELID(i);
                int y = ERID(i);
                dat[x] = LID[i];
                dat[y] = (parent[i] != -1 ? LID[parent[i]] : -1);
            }
        }
        u = ELID(u), v = ELID(v);
        if(u > v) swap(u, v);
        return V[LCA_TABLE.prod(u, v + 1)];
    };
    SegTree<Monoid_1> seg;
    seg.build(N, [](const int& i) { return 0; });
    for(auto&& [x, y] : QRS) {
        auto [ut, vt, w] = edges[x];
        if(LID[ut] < LID[vt]) swap(ut, vt);
        bool flag1 = LID[ut] <= LID[H] && LID[H] < RID[ut];
        bool flag2 = LID[ut] <= LID[y] && LID[y] < RID[ut];
        if(flag1 == flag2) {
            cout << "escaped\n";
        } else {
            cout << "0\n";
        }
    }
}
};
/*
namespace sub4 {
bool check() {
    return true;
}
vector<vector<int>> adj;
vector<int> LID, RID, parent, V, head;
vector<ll> depth;
void dfs1(int u) {
    auto& sz = RID;
    sz[u] = 1;
    int mx = 0;
    for(auto& eid : adj[u]) {
        auto&& [ut, vt, w] = edges[eid];
        int v = (u != ut ? ut : vt);
        if(v == parent[u]) continue;
        parent[v] = u;
        depth[v] = depth[u] + w;
        dfs1(v);
        sz[u] += sz[v];
        if(sz[v] > mx) {
            mx = sz[v];
            swap(eid, adj[u][0]);
        }
    }
}
void dfs2(int u, int& times) {
    LID[u] = times++;
    RID[u] += LID[u];
    V[LID[u]] = u;
    bool heavy = true;
    for(auto&& eid : adj[u]) {
        auto&& [ut, vt, w] = edges[eid];
        int v = (u != ut ? ut : vt);
        if(v == parent[u]) continue;
        head[v] = (heavy ? head[u] : v);
        heavy = false;
        dfs2(v, times);
    }
}
int LCA(int u, int v) {
    for(int i = 25; i--; ) {
        if(LID[u] > LID[v]) swap(u, v);
        if(head[u] == head[v]) return u;
        v = parent[head[v]];
    }
    assert(false);
}
vector<pair<int,int>> get_path_decomposition(int u, int v, bool edge = 0) {
    vector<pair<int,int>> up, down;
    while(true) {
        if(head[u] == head[v]) break;
        if(LID[u] < LID[v]) {
            down.emplace_back(LID[head[v]], LID[v]);
            v = parent[head[v]];
        } else {
            up.emplace_back(LID[u], LID[head[u]]);
            u = parent[head[u]];
        }
    }
    if(LID[u] < LID[v]) down.emplace_back(LID[u] + edge, LID[v]);
    else if(LID[v] + edge <= LID[u]) up.emplace_back(LID[u], LID[v] + edge);
    up.insert(up.end(), down.rbegin(), down.rend());
    return up;
}
void solve() {
    adj.assign(N, vector<int>());
    LID.resize(N);
    RID.resize(N);
    parent.resize(N);
    V.resize(N);
    head.resize(N);
    depth.resize(N);
    for(int i = 0; auto&& [x, y, z] : edges) {
        adj[x].emplace_back(i);
        adj[y].emplace_back(i);
        ++i;
    }
    parent[0] = -1;
    dfs1(0);
    int times = 0;
    head[0] = 0;
    dfs2(0, times);
    SegTree<Monoid_1> seg;
    seg.build(N, [](const int& i) { return 0; });
    for(auto&& [x, y] : QRS) {
        auto [ut, vt, w] = edges[x];
        if(LID[ut] < LID[vt]) swap(ut, vt);
        seg.set(LID[ut], 1);
        bool fl = true;
        [&]() {
            auto pd = get_path_decomposition(H, y, 1);
            for(auto&& [l, r] : pd) {
                if(l > r) swap(l, r);
                if(seg.prod(l, r + 1) != 0) {
                    fl = false;
                    break;
                }
            }
            seg.set(LID[ut], 0);
        } ();
        if(fl) {
            cout << "escaped\n";
        } else {
            ll res = 1e18;
        }
    }
}
};
*/
void solve() {
    cin >> N >> S >> Q >> H;
    --H;
    edges.resize(N - 1);
    QRS.resize(Q);
    villages.resize(S);
    for(auto& [u, v, w] : edges) {
        cin >> u >> v >> w;
        --u, --v;
    }
    for(auto& v : villages) {
        cin >> v;
        --v;
    }
    for(auto& [x, y] : QRS) {
        cin >> x >> y;
        --x, --y;
    }
    if(sub12::check()) return sub12::solve();
    if(sub3::check()) return sub3::solve();
    sub3::solve();
}
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
    while(t--) solve();
}

Compilation message

valley.cpp: In function 'void sub12::solve()':
valley.cpp:37:20: warning: range-based 'for' loops with initializer only available with '-std=c++2a' or '-std=gnu++2a'
   37 |     for(int i = 0; auto&& [x, y, z] : edges) {
      |                    ^~~~
valley.cpp: In function 'void sub3::solve()':
valley.cpp:205:20: warning: range-based 'for' loops with initializer only available with '-std=c++2a' or '-std=gnu++2a'
  205 |     for(int i = 0; auto&& [x, y, z] : edges) {
      |                    ^~~~
valley.cpp:216:10: warning: variable 'lca' set but not used [-Wunused-but-set-variable]
  216 |     auto lca = [&](int u, int v) {
      |          ^~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 604 KB Output is correct
2 Correct 9 ms 604 KB Output is correct
3 Correct 9 ms 604 KB Output is correct
4 Correct 9 ms 604 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 604 KB Output is correct
2 Correct 9 ms 604 KB Output is correct
3 Correct 9 ms 604 KB Output is correct
4 Correct 9 ms 604 KB Output is correct
5 Correct 5 ms 348 KB Output is correct
6 Correct 7 ms 568 KB Output is correct
7 Correct 14 ms 600 KB Output is correct
8 Correct 5 ms 572 KB Output is correct
9 Correct 9 ms 344 KB Output is correct
10 Correct 14 ms 348 KB Output is correct
11 Correct 6 ms 584 KB Output is correct
12 Correct 7 ms 348 KB Output is correct
13 Correct 14 ms 600 KB Output is correct
14 Correct 12 ms 588 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 60 ms 15360 KB Output is correct
2 Correct 69 ms 16720 KB Output is correct
3 Correct 67 ms 16720 KB Output is correct
4 Correct 65 ms 18904 KB Output is correct
5 Correct 64 ms 18772 KB Output is correct
6 Correct 73 ms 23712 KB Output is correct

Subtask #4
0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 604 KB Output is correct
2 Correct 9 ms 604 KB Output is correct
3 Correct 9 ms 604 KB Output is correct
4 Correct 9 ms 604 KB Output is correct
5 Correct 5 ms 348 KB Output is correct
6 Correct 7 ms 568 KB Output is correct
7 Correct 14 ms 600 KB Output is correct
8 Correct 5 ms 572 KB Output is correct
9 Correct 9 ms 344 KB Output is correct
10 Correct 14 ms 348 KB Output is correct
11 Correct 6 ms 584 KB Output is correct
12 Correct 7 ms 348 KB Output is correct
13 Correct 14 ms 600 KB Output is correct
14 Correct 12 ms 588 KB Output is correct
15 Correct 60 ms 15360 KB Output is correct
16 Correct 69 ms 16720 KB Output is correct
17 Correct 67 ms 16720 KB Output is correct
18 Correct 65 ms 18904 KB Output is correct
19 Correct 64 ms 18772 KB Output is correct
20 Correct 73 ms 23712 KB Output is correct
21 Incorrect 51 ms 16208 KB Output isn't correct
22 Halted 0 ms 0 KB -