結果
| 問題 |
No.1326 ふたりのDominator
|
| コンテスト | |
| ユーザー |
 haruki_K
|
| 提出日時 | 2021-01-21 16:55:19 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 147 ms / 2,000 ms |
| コード長 | 12,160 bytes |
| コンパイル時間 | 2,925 ms |
| コンパイル使用メモリ | 229,192 KB |
| 最終ジャッジ日時 | 2025-01-18 03:06:50 |
|
ジャッジサーバーID （参考情報） |
judge1 / judge1 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 1 |
| other | AC * 24 |
ソースコード
// >>> TEMPLATES
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using i32 = int32_t;
using i64 = int64_t;
using u32 = uint32_t;
using u64 = uint64_t;
#define int ll
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define repR(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define rep1R(i, n) for (int i = (int)(n); i >= 1; i--)
#define loop(i, a, B) for (int i = a; i B; i++)
#define loopR(i, a, B) for (int i = a; i B; i--)
#define all(x) begin(x), end(x)
#define allR(x) rbegin(x), rend(x)
#define rng(x, l, r) begin(x) + (l), begin(x) + (r)
#define pb push_back
#define eb emplace_back
#define fst first
#define snd second
template <class A, class B> auto mp(A &&a, B &&b) { return make_pair(forward<A>(a), forward<B>(b)); }
template <class... T> auto mt(T&&... x) { return make_tuple(forward<T>(x)...); }
template <class Int> auto constexpr inf_ = numeric_limits<Int>::max()/2-1;
auto constexpr INF32 = inf_<int32_t>;
auto constexpr INF64 = inf_<int64_t>;
auto constexpr INF = inf_<int>;
#ifdef LOCAL
#include "debug.hpp"
#else
#define dump(...) (void)(0)
#define say(x) (void)(0)
#define debug if (0)
#endif
template <class T, class Comp> struct pque : priority_queue<T, vector<T>, Comp> { vector<T> &data() { return this->c; } void clear() { this->c.clear(); } };
template <class T> using pque_max = pque<T, less<T>>;
template <class T> using pque_min = pque<T, greater<T>>;
template <class T, class = typename T::iterator, enable_if_t<!is_same<T, string>::value, int> = 0>
ostream& operator<<(ostream& os, T const& a) { bool f = true; for (auto const& x : a) os << (f ? "" : " ") << x, f = false; return os; }
template <class T, size_t N, enable_if_t<!is_same<T, char>::value, int> = 0>
ostream& operator<<(ostream& os, const T (&a)[N]) { bool f = true; for (auto const& x : a) os << (f ? "" : " ") << x, f = false; return os; }
template <class T, class = decltype(begin(declval<T&>())), class = typename enable_if<!is_same<T, string>::value>::type>
istream& operator>>(istream& is, T &a) { for (auto& x : a) is >> x; return is; }
template <class T, class S> ostream& operator<<(ostream& os, pair<T, S> const& p) { return os << p.first << " " << p.second; }
template <class T, class S> istream& operator>>(istream& is, pair<T, S>& p) { return is >> p.first >> p.second; }
struct IOSetup { IOSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } iosetup;
template <class F> struct FixPoint : private F {
constexpr FixPoint(F&& f) : F(forward<F>(f)) {}
template <class... T> constexpr auto operator()(T&&... x) const { return F::operator()(*this, forward<T>(x)...); }
};
struct MakeFixPoint { template <class F> constexpr auto operator|(F&& f) const { return FixPoint<F>(forward<F>(f)); } };
#define MFP MakeFixPoint()|
#define def(name, ...) auto name = MFP [&](auto &&name, __VA_ARGS__)
template <class T, size_t d> struct vec_impl {
using type = vector<typename vec_impl<T, d-1>::type>;
template <class... U> static type make_v(size_t n, U&&... x) { return type(n, vec_impl<T, d-1>::make_v(forward<U>(x)...)); }
};
template <class T> struct vec_impl<T, 0> { using type = T; static type make_v(T const& x = {}) { return x; } };
template <class T, size_t d = 1> using vec = typename vec_impl<T, d>::type;
template <class T, size_t d = 1, class... Args> auto make_v(Args&&... args) { return vec_impl<T, d>::make_v(forward<Args>(args)...); }
template <class T> void quit(T const& x) { cout << x << endl; exit(0); }
template <class T, class U> constexpr bool chmin(T& x, U const& y) { if (x > y) { x = y; return true; } return false; }
template <class T, class U> constexpr bool chmax(T& x, U const& y) { if (x < y) { x = y; return true; } return false; }
template <class It> constexpr auto sumof(It b, It e) { return accumulate(b, e, typename iterator_traits<It>::value_type{}); }
template <class T> int sz(T const& x) { return x.size(); }
template <class C, class T> int lbd(C const& v, T const& x) { return lower_bound(begin(v), end(v), x)-begin(v); }
template <class C, class T> int ubd(C const& v, T const& x) { return upper_bound(begin(v), end(v), x)-begin(v); }
const int dx[] = { 1, 0, -1, 0, 1, -1, -1, 1 };
const int dy[] = { 0, 1, 0, -1, 1, 1, -1, -1 };
constexpr int popcnt(ll x) { return __builtin_popcountll(x); }
template <class A, class B> pair<A, B> operator+(pair<A, B> const& p, pair<A, B> const& q) { return { p.first + q.first, p.second + q.second }; }
template <class A, class B> pair<A, B> operator-(pair<A, B> const& p, pair<A, B> const& q) { return { p.first - q.first, p.second - q.second }; }
mt19937_64 seed_{random_device{}()};
template <class Int> Int rand(Int a, Int b) { return uniform_int_distribution<Int>(a, b)(seed_); }
i64 irand(i64 a, i64 b) { return rand<i64>(a, b); } // [a, b]
u64 urand(u64 a, u64 b) { return rand<u64>(a, b); } //
template <class It> void shuffle(It l, It r) { shuffle(l, r, seed_); }
// <<<
// >>> block cut tree
#ifndef EDGE_INFO
#define EDGE_INFO
constexpr int dest(int v) { return v; }
template <class E, class = decltype(declval<E>().to)>
constexpr int dest(E const& e) { return e.to; }
constexpr int cost(int) { return 1; }
template <class E, class = decltype(declval<E>().cost)>
constexpr auto cost(E const& e) { return e.cost; }
template <class E> using cost_t = decltype(cost(declval<E>()));
#endif
template <class E> struct BlockCutTree {
const int n;
vector<vector<pair<int, int>>> block; // pair : minmax
vector<int> cut; // cut vertecies
vector<int> id; // not cut and in kth blcok -> k, kth cut -> block.size() + k
vector<vector<int>> tree; // block cut tree
BlockCutTree(vector<vector<E>> const& g) : n(g.size()) {
build_block_cut(g);
build_id_tree();
}
bool is_cut(int x) const { return id[x] >= (int)block.size(); }
void build_block_cut(vector<vector<E>> const& g) {
using i32 = int32_t;
i32 time = 0;
vector<i32> ord(n, -1), low(n);
vector<pair<int32_t, int32_t>> st;
auto dfs = [&](auto dfs, i32 x, i32 p) -> void {
low[x] = ord[x] = time++;
i32 ch = 0;
bool is_cut = false;
for (auto const& e : g[x]) {
const i32 y = dest(e);
if (y == p or ord[y] >= ord[x]) continue;
st.emplace_back(minmax(x, y));
if (ord[y] >= 0) {
chmin(low[x], ord[y]);
continue;
}
ch++;
dfs(dfs, y, x);
chmin(low[x], low[y]);
if (low[y] >= ord[x]) {
is_cut |= p >= 0;
i32 i = st.size();
const pair<i32, i32> xy = minmax(x, y);
while (--i >= 0 and st[i] != xy) { }
block.emplace_back(st.begin() + i, st.end());
st.resize(i);
}
}
is_cut |= p < 0 and ch > 1;
if (is_cut) cut.push_back(x);
};
rep (x, g.size()) if (ord[x] < 0) dfs(dfs, x, -1);
reverse(block.begin(), block.end());
}
void build_id_tree() {
const int32_t B = block.size(), C = cut.size();
vector<int32_t> last(C, -1);
id.resize(n, -1);
tree.resize(B+C);
rep (i, C) id[cut[i]] = B + i;
rep (i, B) for (auto [x, y] : block[i]) {
for (int v : {x, y}) {
if (id[v] < B) {
id[v] = i;
} else if (exchange(last[id[v]-B], i) < i) {
tree[i].push_back(id[v]);
tree[id[v]].push_back(i);
}
}
}
}
};
// <<<
// >>> LCA (RMQ)
#ifndef EDGE_INFO
#define EDGE_INFO
constexpr int dest(int v) { return v; }
template <class E, class = decltype(declval<E>().to)>
constexpr int dest(E const& e) { return e.to; }
constexpr int cost(int) { return 1; }
template <class E, class = decltype(declval<E>().cost)>
constexpr auto cost(E const& e) { return e.cost; }
template <class E> using cost_t = decltype(cost(declval<E>()));
#endif
template <class E, class RMQ> struct LCA {
vector<vector<E>> const* g;
int32_t n, root;
vector<int32_t> id;
vector<cost_t<E>> d;
RMQ rmq;
LCA() {}
LCA(vector<vector<E>> const* g, int root)
: g(g), n(g->size()), root(root), id(n), d(n) {
vector<pair<int, int>> a;
a.reserve(n-1);
auto dfs = [&](auto dfs, int x, int p, int d0, cost_t<E> d1) -> void {
id[x] = a.size();
d[x] = d1;
for (auto const& e : (*g)[x]) {
if (dest(e) == p) continue;
a.emplace_back(d0, x);
dfs(dfs, dest(e), x, d0 + 1, d1 + cost(e));
}
};
dfs(dfs, root, -1, 0, 0);
rmq = RMQ(a);
}
cost_t<E> dep(int a) const { return d[a]; }
int operator()(int a, int b) const { return lca(a, b); }
int lca(int a, int b) const {
if (a == b) return a;
if (id[a] > id[b]) swap(a, b);
return rmq.get(id[a], id[b]).second;
}
cost_t<E> dist(int a, int b) const { return d[a] + d[b] - 2*d[lca(a, b)]; }
};
namespace RMQ {
// >>> DST
template <class Handler>
struct DST : Handler {
using Value = typename Handler::Value;
using Handler::unit; // () -> Value
using Handler::merge; // (Value, Value) -> Value
static constexpr int bsr(int32_t x) { return x ? 31-__builtin_clz(x) : -1; }
vector<vector<Value>> v;
DST() {}
template <class... T> DST(T&&... x) { build(forward<T>(x)...); }
void build(int n) { build(n, unit()); }
void build(int n, Value const& x) { build(n, [&](int) { return x; }); }
void build(vector<Value> const& v) { build(v.size(), [&](int i) { return v[i]; }); }
template <class F, class = decltype(declval<F>()(0))>
void build(int n, F gen) {
assert(n >= 0);
v.resize(1);
v[0].resize(n, unit());
for (int i = 0; i < n; i++) v[0][i] = gen(i);
if (n <= 1) return;
const int lg = __lg(2*n-1);
v.resize(lg, vector<Value>(n, unit()));
for (int h = 1; h < lg; ++h) {
const int w = 1<<h;
for (int b = w; b < n; b += (w<<1)) {
Value x = unit();
for (int j = b-1; j >= b-w; --j) {
v[h][j] = x = merge(v[0][j], x);
}
x = unit();
for (int j = b; j < min(n, b+w); ++j) {
v[h][j] = x = merge(x, v[0][j]);
}
}
}
}
int size() const { return v.empty() ? 0 : v[0].size(); }
Value get(int l, int r) const {
assert(0 <= l); assert(l <= r); assert(r <= size());
if (l == r) return unit();
--r;
if (l == r) return v[0][l];
const int h = bsr(l^r);
return merge(v[h][l], v[h][r]);
}
Value operator[](int idx) const {
assert(0 <= idx); assert(idx < size());
return v[0][idx];
}
};
// <<<
struct Min {
using Value = pair<int, int>;
static constexpr auto inf = numeric_limits<int>::max();
constexpr static Value unit() { return { inf, inf }; }
constexpr static Value merge(Value const& x, Value const& y) { return min(x, y); }
};
using RMQ = DST<Min>;
}
template <class E>
auto get_lca(vector<vector<E>> const& g, int root = 0) {
return LCA<E, RMQ::RMQ>(&g, root);
}
// <<<
int32_t main() {
int n, m; cin >> n >> m;
vector<vector<int>> g(n);
rep (i, m) {
int a, b; cin >> a >> b;
--a, --b;
g[a].eb(b);
g[b].eb(a);
}
auto bc = BlockCutTree(g);
auto lca = get_lca(bc.tree);
int q; cin >> q;
rep (_, q) {
int x, y; cin >> x >> y; x--, y--;
if (x == y) {
cout << 0 << "\n";
} else {
int d = lca.dist(bc.id[x], bc.id[y]);
if (bc.is_cut(x)) d--;
if (bc.is_cut(y)) d--;
assert(d % 2 == 0);
cout << d/2 << "\n";
}
}
}