#line 1 "test/yukicoder/922/main.test.cpp"
#define PROBLEM "https://yukicoder.me/problems/no/922"
#include <iostream>
#include <utility>
#include <vector>
#line 4 "Mylib/Graph/Template/graph.cpp"
namespace haar_lib {
template <typename T>
struct edge {
int from, to;
T cost;
int index = -1;
edge() {}
edge(int from, int to, T cost) : from(from), to(to), cost(cost) {}
edge(int from, int to, T cost, int index) : from(from), to(to), cost(cost), index(index) {}
};
template <typename T>
struct graph {
using weight_type = T;
using edge_type = edge<T>;
std::vector<std::vector<edge<T>>> data;
auto& operator[](size_t i) { return data[i]; }
const auto& operator[](size_t i) const { return data[i]; }
auto begin() const { return data.begin(); }
auto end() const { return data.end(); }
graph() {}
graph(int N) : data(N) {}
bool empty() const { return data.empty(); }
int size() const { return data.size(); }
void add_edge(int i, int j, T w, int index = -1) {
data[i].emplace_back(i, j, w, index);
}
void add_undirected(int i, int j, T w, int index = -1) {
add_edge(i, j, w, index);
add_edge(j, i, w, index);
}
template <size_t I, bool DIRECTED = true, bool WEIGHTED = true>
void read(int M) {
for (int i = 0; i < M; ++i) {
int u, v;
std::cin >> u >> v;
u -= I;
v -= I;
T w = 1;
if (WEIGHTED) std::cin >> w;
if (DIRECTED)
add_edge(u, v, w, i);
else
add_undirected(u, v, w, i);
}
}
};
template <typename T>
using tree = graph<T>;
} // namespace haar_lib
#line 2 "Mylib/Graph/TreeUtils/forest.cpp"
#include <algorithm>
#line 6 "Mylib/Graph/TreeUtils/forest.cpp"
namespace haar_lib {
template <typename T>
class forest {
std::vector<tree<T>> trees_;
std::vector<int> tree_id_, vertex_id_;
std::vector<std::vector<int>> rid_;
public:
forest() {}
forest(const graph<T> &g) {
const int N = g.size();
tree_id_.resize(N);
vertex_id_.resize(N);
std::vector<bool> check(N);
auto dfs =
[&](auto &dfs, int cur, std::vector<int> &vertices, std::vector<edge<T>> &edges) -> void {
check[cur] = true;
vertices.push_back(cur);
for (auto &e : g[cur]) {
edges.push_back(e);
if (not check[e.to]) {
dfs(dfs, e.to, vertices, edges);
}
}
};
for (int i = 0; i < N; ++i) {
if (not check[i]) {
std::vector<int> vertices;
std::vector<edge<T>> edges;
dfs(dfs, i, vertices, edges);
const int m = vertices.size();
const int k = trees_.size();
rid_.emplace_back(m);
for (int i = 0; i < (int) vertices.size(); ++i) {
tree_id_[vertices[i]] = k;
vertex_id_[vertices[i]] = i;
rid_[k][i] = vertices[i];
}
trees_.push_back(m);
for (auto &e : edges) {
trees_[k].add_edge(vertex_id_[e.from], vertex_id_[e.to], e.cost);
}
}
}
}
const auto &trees() const { return trees_; }
auto id(int i) const { return std::make_pair(tree_id_[i], vertex_id_[i]); }
int tree_id(int i) const { return tree_id_[i]; }
int vertex_id(int i) const { return vertex_id_[i]; }
int rid(int t, int u) const { return rid_[t][u]; }
bool in_same_tree(int i, int j) const {
return tree_id_[i] == tree_id_[j];
}
};
} // namespace haar_lib
#line 2 "Mylib/Graph/TreeUtils/lca_doubling.cpp"
#include <cmath>
#line 5 "Mylib/Graph/TreeUtils/lca_doubling.cpp"
namespace haar_lib {
template <typename T>
class lowest_common_ancestor_doubling {
int n_, log2n_;
std::vector<std::vector<int>> parent_;
std::vector<int> depth_;
void dfs(const tree<T> &tr, int cur, int par, int d) {
parent_[cur][0] = par;
depth_[cur] = d;
for (auto &e : tr[cur]) {
if (e.to != par) {
dfs(tr, e.to, cur, d + 1);
}
}
}
public:
lowest_common_ancestor_doubling() {}
lowest_common_ancestor_doubling(const tree<T> &tr, int root) : n_(tr.size()), log2n_((int) ceil(log2(n_)) + 1), parent_(n_, std::vector<int>(log2n_)), depth_(n_) {
dfs(tr, root, -1, 0);
for (int k = 0; k < log2n_ - 1; ++k) {
for (int v = 0; v < n_; ++v) {
if (parent_[v][k] == -1)
parent_[v][k + 1] = -1;
else
parent_[v][k + 1] = parent_[parent_[v][k]][k];
}
}
}
int lca(int a, int b) const {
if (depth_[a] >= depth_[b]) std::swap(a, b);
for (int k = 0; k < log2n_; ++k) {
if ((depth_[b] - depth_[a]) >> k & 1) b = parent_[b][k];
}
if (a == b) return a;
for (int k = log2n_; --k >= 0;) {
if (parent_[a][k] != parent_[b][k]) {
a = parent_[a][k];
b = parent_[b][k];
}
}
return parent_[a][0];
}
int operator()(int a, int b) const { return lca(a, b); }
T distance(int u, int v, const std::vector<T> &dist) const {
return dist[u] + dist[v] - 2 * dist[lca(u, v)];
}
};
} // namespace haar_lib
#line 4 "Mylib/Graph/TreeUtils/rerooting.cpp"
namespace haar_lib {
namespace rerooting_impl {
template <typename T, typename U, typename Merge, typename EdgeF, typename VertexF>
T rec1(
tree<U> &tr,
T id,
const Merge &merge,
const EdgeF &f,
const VertexF &g,
std::vector<std::vector<T>> &dp,
int cur,
int par = -1) {
T acc = id;
for (int i = 0; i < (int) tr[cur].size(); ++i) {
auto &e = tr[cur][i];
if (e.to == par) continue;
dp[cur][i] = rec1(tr, id, merge, f, g, dp, e.to, cur);
acc = merge(acc, f(dp[cur][i], e));
}
return g(acc, cur);
}
template <typename T, typename U, typename Merge, typename EdgeF, typename VertexF>
void rec2(
const tree<U> &tr,
T id,
const Merge &merge,
const EdgeF &f,
const VertexF &g,
std::vector<std::vector<T>> &dp,
int cur,
int par,
T value) {
const int l = tr[cur].size();
for (int i = 0; i < l; ++i) {
if (tr[cur][i].to == par) {
dp[cur][i] = value;
}
}
std::vector<T> left(l + 1, id), right(l + 1, id);
for (int i = 0; i < l - 1; ++i) {
const auto &e = tr[cur][i];
left[i + 1] = merge(left[i], f(dp[cur][i], e));
}
for (int i = l - 1; i >= 1; --i) {
const auto &e = tr[cur][i];
right[i - 1] = merge(right[i], f(dp[cur][i], e));
}
for (int i = 0; i < l; ++i) {
const auto &e = tr[cur][i];
if (e.to == par) continue;
rec2(tr, id, merge, f, g, dp, e.to, cur, g(merge(left[i], right[i]), cur));
}
}
} // namespace rerooting_impl
template <typename T, typename U, typename Merge, typename EdgeF, typename VertexF>
auto rerooting(tree<U> tr, T id, Merge merge, EdgeF f, VertexF g) {
const int N = tr.size();
std::vector<std::vector<T>> dp(N);
std::vector<T> ret(N, id);
for (int i = 0; i < N; ++i) dp[i].assign(tr[i].size(), id);
rerooting_impl::rec1(tr, id, merge, f, g, dp, 0);
rerooting_impl::rec2(tr, id, merge, f, g, dp, 0, -1, id);
for (int i = 0; i < N; ++i) {
for (int j = 0; j < (int) tr[i].size(); ++j) {
ret[i] = merge(ret[i], f(dp[i][j], tr[i][j]));
}
ret[i] = g(ret[i], i);
}
return ret;
}
} // namespace haar_lib
#line 2 "Mylib/Graph/TreeUtils/tree_distance.cpp"
#include <stack>
#line 5 "Mylib/Graph/TreeUtils/tree_distance.cpp"
namespace haar_lib {
template <typename T>
std::vector<T> tree_distance(const tree<T> &tr, int root) {
const int n = tr.size();
std::vector<T> ret(n);
std::vector<bool> visited(n);
std::stack<int> st;
st.push(root);
ret[root] = 0;
while (not st.empty()) {
int cur = st.top();
st.pop();
visited[cur] = true;
for (auto &e : tr[cur]) {
if (not visited[e.to]) {
ret[e.to] = ret[cur] + e.cost;
st.push(e.to);
}
}
}
return ret;
}
} // namespace haar_lib
#line 2 "Mylib/IO/input_tuples.cpp"
#include <initializer_list>
#line 4 "Mylib/IO/input_tuples.cpp"
#include <tuple>
#line 6 "Mylib/IO/input_tuple.cpp"
namespace haar_lib {
template <typename T, size_t... I>
static void input_tuple_helper(std::istream &s, T &val, std::index_sequence<I...>) {
(void) std::initializer_list<int>{(void(s >> std::get<I>(val)), 0)...};
}
template <typename T, typename U>
std::istream &operator>>(std::istream &s, std::pair<T, U> &value) {
s >> value.first >> value.second;
return s;
}
template <typename... Args>
std::istream &operator>>(std::istream &s, std::tuple<Args...> &value) {
input_tuple_helper(s, value, std::make_index_sequence<sizeof...(Args)>());
return s;
}
} // namespace haar_lib
#line 8 "Mylib/IO/input_tuples.cpp"
namespace haar_lib {
template <typename... Args>
class InputTuples {
struct iter {
using value_type = std::tuple<Args...>;
value_type value;
bool fetched = false;
int N, c = 0;
value_type operator*() {
if (not fetched) {
std::cin >> value;
}
return value;
}
void operator++() {
++c;
fetched = false;
}
bool operator!=(iter &) const {
return c < N;
}
iter(int N) : N(N) {}
};
int N;
public:
InputTuples(int N) : N(N) {}
iter begin() const { return iter(N); }
iter end() const { return iter(N); }
};
template <typename... Args>
auto input_tuples(int N) {
return InputTuples<Args...>(N);
}
} // namespace haar_lib
#line 12 "test/yukicoder/922/main.test.cpp"
namespace hl = haar_lib;
int main() {
int N, M, Q;
std::cin >> N >> M >> Q;
hl::graph<int64_t> g(N);
g.read<1, false, false>(M);
int64_t ans = 0;
hl::forest<int64_t> forest(g);
const int tree_num = forest.trees().size();
std::vector<hl::lowest_common_ancestor_doubling<int64_t>> lcas(tree_num);
std::vector<std::vector<int64_t>> dists(tree_num);
for (int i = 0; i < tree_num; ++i) {
lcas[i] = hl::lowest_common_ancestor_doubling(forest.trees()[i], 0);
dists[i] = hl::tree_distance(forest.trees()[i], 0);
}
std::vector<std::vector<int>> plans(tree_num);
for (int i = 0; i < tree_num; ++i) {
plans[i] = std::vector<int>(forest.trees()[i].size());
}
for (auto [a, b] : hl::input_tuples<int, int>(Q)) {
--a, --b;
if (forest.in_same_tree(a, b)) {
ans += lcas[forest.tree_id(a)].distance(forest.vertex_id(a), forest.vertex_id(b), dists[forest.tree_id(a)]);
} else {
plans[forest.tree_id(a)][forest.vertex_id(a)] += 1;
plans[forest.tree_id(b)][forest.vertex_id(b)] += 1;
}
}
for (int i = 0; i < tree_num; ++i) {
const auto &tree = forest.trees()[i];
const auto &plan = plans[i];
auto res =
hl::rerooting<std::pair<int, int>>(
tree,
std::make_pair(0, 0),
[](const auto &a, const auto &b) {
return std::make_pair(a.first + b.first, a.second + b.second);
},
[](const auto &x, const auto &e) {
return std::make_pair(x.first, x.second + x.first);
},
[&](const auto &x, int v) {
return std::make_pair(x.first + plan[v], x.second);
});
ans +=
std::min_element(
res.begin(),
res.end(),
[](const auto &a, const auto &b) {
return a.second < b.second;
})
->second;
}
std::cout << ans << std::endl;
return 0;
}
test/yukicoder/922/main.test.cpp
Basic graph
(Mylib/Graph/Template/graph.cpp)