#[allow(unused_imports)] use std::cmp::*; #[allow(unused_imports)] use std::collections::*; use std::io::{Write, BufWriter}; // https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 macro_rules! input { ($($r:tt)*) => { let stdin = std::io::stdin(); let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock())); let mut next = move || -> String{ bytes .by_ref() .map(|r|r.unwrap() as char) .skip_while(|c|c.is_whitespace()) .take_while(|c|!c.is_whitespace()) .collect() }; input_inner!{next, $($r)*} }; } macro_rules! input_inner { ($next:expr) => {}; ($next:expr, ) => {}; ($next:expr, $var:ident : $t:tt $($r:tt)*) => { let $var = read_value!($next, $t); input_inner!{$next $($r)*} }; } macro_rules! read_value { ($next:expr, ( $($t:tt),* )) => { ( $(read_value!($next, $t)),* ) }; ($next:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($next, $t)).collect::>() }; ($next:expr, chars) => { read_value!($next, String).chars().collect::>() }; ($next:expr, usize1) => { read_value!($next, usize) - 1 }; ($next:expr, [ $t:tt ]) => {{ let len = read_value!($next, usize); (0..len).map(|_| read_value!($next, $t)).collect::>() }}; ($next:expr, $t:ty) => { $next().parse::<$t>().expect("Parse error") }; } #[allow(unused)] macro_rules! debug { ($($format:tt)*) => (write!(std::io::stderr(), $($format)*).unwrap()); } #[allow(unused)] macro_rules! debugln { ($($format:tt)*) => (writeln!(std::io::stderr(), $($format)*).unwrap()); } /** * Union-Find tree. * Verified by https://atcoder.jp/contests/pakencamp-2019-day3/submissions/9253305 */ struct UnionFind { disj: Vec, rank: Vec } impl UnionFind { fn new(n: usize) -> Self { let disj = (0..n).collect(); UnionFind { disj: disj, rank: vec![1; n] } } fn root(&mut self, x: usize) -> usize { if x != self.disj[x] { let par = self.disj[x]; let r = self.root(par); self.disj[x] = r; } self.disj[x] } fn unite(&mut self, x: usize, y: usize) { let mut x = self.root(x); let mut y = self.root(y); if x == y { return } if self.rank[x] > self.rank[y] { std::mem::swap(&mut x, &mut y); } self.disj[x] = y; self.rank[y] += self.rank[x]; } #[allow(unused)] fn is_same_set(&mut self, x: usize, y: usize) -> bool { self.root(x) == self.root(y) } #[allow(unused)] fn size(&mut self, x: usize) -> usize { let x = self.root(x); self.rank[x] } } /// Lowest Common Ancestor. Call lca(x, y) to get the lca of them. pub struct LowestCommonAncestor { n: usize, bn: usize, parent: Vec, // r is root <=> parent[r] = r dep: Vec, lca_tbl: Vec> } impl LowestCommonAncestor { fn dfs(&mut self, edges: &[Vec], v: usize, par: usize, d: usize) { self.parent[v] = par; self.dep[v] = d; for &u in edges[v].iter() { if u != par { self.dfs(edges, u, v, d + 1); } } } fn lca_init(&mut self) { let n = self.n; for v in 0 .. n { self.lca_tbl[v] = vec![0; self.bn + 1]; self.lca_tbl[v][0] = self.parent[v]; } for i in 1 .. self.bn + 1 { for v in 0 .. n { self.lca_tbl[v][i] = self.lca_tbl[self.lca_tbl[v][i - 1]][i - 1]; } } } pub fn lca(&self, mut x: usize, mut y: usize) -> usize { let dx = self.dep[x]; let mut dy = self.dep[y]; if dx > dy { return self.lca(y, x); } for l in (0 .. self.bn + 1).rev() { if dy - dx >= 1 << l { y = self.lca_tbl[y][l]; dy -= 1 << l; } } assert_eq!(dx, dy); if x == y { return x; } for l in (0 .. self.bn + 1).rev() { if self.lca_tbl[x][l] != self.lca_tbl[y][l] { x = self.lca_tbl[x][l]; y = self.lca_tbl[y][l]; } } self.lca_tbl[x][0] } #[allow(unused)] pub fn depth(&self, a: usize) -> usize { self.dep[a] } #[allow(unused)] pub fn parent(&self, a: usize) -> usize { self.parent[a] } pub fn new(edges: &[Vec], roots: &[usize]) -> Self { let n = edges.len(); let bn = (n.next_power_of_two() - 1).count_ones() as usize; let mut ret = LowestCommonAncestor { n: n, bn: bn, parent: vec![0; n], dep: vec![0; n], lca_tbl: vec![Vec::new(); n] }; for &r in roots { ret.dfs(edges, r, r, 0); } ret.lca_init(); ret } } #[derive(Copy, Clone, Debug)] struct D { cnt: i64, sum: i64, } impl D { fn new(cnt: i64, sum: i64) -> D { D { cnt: cnt, sum: sum, } } fn mv(self, dist: i64) -> D { D { cnt: self.cnt, sum: self.sum + self.cnt * dist, } } fn add(self, x: D) -> D { D { cnt: self.cnt + x.cnt, sum: self.sum + x.sum, } } fn sub(self, x: D) -> D { D { cnt: self.cnt - x.cnt, sum: self.sum - x.sum, } } } fn dfs1(v: usize, vis: &mut [bool], g: &[Vec], qs: &[i64], ds: &mut [D]) -> D { if vis[v] { return D::new(0, 0); } vis[v] = true; let mut cur = D::new(qs[v], 0); for &w in &g[v] { let sub = dfs1(w, vis, g, qs, ds); cur = cur.add(sub.mv(1)); } ds[v] = cur; cur } fn dfs2(v: usize, par: usize, g: &[Vec], qs: &[i64], ds: &[D], cur_par: D) -> i64 { let mut mi = ds[v].sum + cur_par.sum; for &w in &g[v] { if w == par { continue; } let sub_cur_par = cur_par.add(ds[v]).sub(ds[w].mv(1)).mv(1); let sub = dfs2(w, v, g, qs, ds, sub_cur_par); mi = min(mi, sub); } mi } fn solve() { let out = std::io::stdout(); let mut out = BufWriter::new(out.lock()); macro_rules! puts { ($($format:tt)*) => (write!(out,$($format)*).unwrap()); } input! { n: usize, m: usize, q: usize, uv: [(usize1, usize1); m], ab: [(usize1, usize1); q], } let mut uf = UnionFind::new(n); let mut g = vec![vec![]; n]; for &(u, v) in &uv { uf.unite(u, v); g[u].push(v); g[v].push(u); } let mut qs = vec![0; n]; let mut same_set = vec![]; for &(a, b) in &ab { if uf.is_same_set(a, b) { same_set.push((a, b)); } else { qs[a] += 1; qs[b] += 1; } } let mut vis = vec![false; n]; let mut ds = vec![D::new(0, 0); n]; let mut tot = 0; let mut roots = vec![]; for i in 0..n { if !vis[i] { dfs1(i, &mut vis, &g, &qs, &mut ds); tot += dfs2(i, n, &g, &qs, &ds, D::new(0, 0)); roots.push(i); } } let lca = LowestCommonAncestor::new(&g, &roots); for &(a, b) in &same_set { let l = lca.lca(a, b); tot += (lca.dep[a] + lca.dep[b] - 2 * lca.dep[l]) as i64; } debugln!("{:?}", same_set); debugln!("qs = {:?}", qs); debugln!("ds = {:?}", ds); puts!("{}\n", tot); } fn main() { // In order to avoid potential stack overflow, spawn a new thread. let stack_size = 104_857_600; // 100 MB let thd = std::thread::Builder::new().stack_size(stack_size); thd.spawn(|| solve()).unwrap().join().unwrap(); }