#line 1 "test/graph/dm/yuki1745.test.cpp" #define PROBLEM "https://yukicoder.me/problems/no/1745" #line 2 "src/graph/BipartiteMatching.hpp" #line 2 "src/Template.hpp" #define CUT #include using namespace std; #define rep(i, l, r) for (int i = (l); i < (r); ++i) #define rrep(i, l, r) for (int i = (r); i --> (l);) #define all(c) begin(c), end(c) #ifdef LOCAL #define debug(...) debug_impl(#__VA_ARGS__, __VA_ARGS__) template void debug_impl(string s, H&& h, Ts&&... ts) { cerr << '(' << s << "): (" << forward(h); ((cerr << ", " << forward(ts)), ..., (cerr << ")\n")); } #else #define debug(...) void(0) #endif template bool chmax(T& a, const T& b) { return b > a ? (a = b, true) : false; } template bool chmin(T& a, const T& b) { return b < a ? (a = b, true) : false; } template istream& operator>>(istream& in, vector& v) { for (auto& e : v) in >> e; return in; } template void read(Args&... args) { (cin >> ... >> args); } template ostream& operator<<(ostream& out, const vector& v) { int n = v.size(); rep(i, 0, n) { out << v[i]; if (i + 1 != n) out << ' '; } return out; } template void print(H&& h, Ts &&... ts) { cout << h, ((cout << ' ' << forward(ts)), ..., (cout << '\n')); } struct io_setup_ { io_setup_() { ios::sync_with_stdio(false), cin.tie(nullptr); cout << fixed << setprecision(10); } } io_setup{}; #undef CUT #define NOTE compile command: \texttt{g++ -std=gnu++17 -Wall -Wextra -g -fsanitize=address -fsanitize=undefined \$\{file\} -o \$\{fileDirname\}/\$\{fileBasenameNoExtension\}} #undef NOTE #define NOTE \texttt{-DLOCAL} を加えると \texttt{debug(...)} による出力が有効となる #undef NOTE #line 4 "src/graph/BipartiteMatching.hpp" #define CUT vector bipartite_matching(const vector>& g) { const int n = g.size(); vector res(n, -1); vector use(n); auto dfs = [&](auto dfs, int v) { if (exchange(use[v], true)) return false; for (auto u : g[v]) if (res[u] < 0 or dfs(dfs, res[u])) { return res[u] = v, res[v] = u, true; } return false; }; for (bool upd = true; exchange(upd, false);) { use.assign(n, false); rep(v, 0, n) upd |= res[v] == -1 and dfs(dfs, v); } return res; } #undef CUT #line 3 "src/graph/DMDecomp.hpp" #define CUT #line 2 "src/graph/SCC.hpp" #line 4 "src/graph/SCC.hpp" #define CUT // Returns (# of SCC, SCC id) (id: topological order) pair> scc_ids(const vector>& g) { int n = g.size(); int num = 0; int t = 0; vector cmp, low(n), ord(n, -1), id(n); cmp.reserve(n); auto dfs = [&](auto self, int v) -> void { low[v] = ord[v] = t++; cmp.push_back(v); for (int to : g[v]) { if (ord[to] == -1) { self(self, to); chmin(low[v], low[to]); } else { chmin(low[v], ord[to]); } } if (low[v] != ord[v]) return; while (true) { int u = cmp.back(); cmp.pop_back(); ord[u] = n; id[u] = num; if (u == v) break; } num++; }; rep(i, 0, n) if (ord[i] == -1) dfs(dfs, i); for (auto& x : id) x = num - 1 - x; return { num, id }; } // Return vector of SCCs in topological order vector> scc(const vector>& g) { auto [k, ids] = scc_ids(g); vector> cmps(k); int n = g.size(); rep(i, 0, n) cmps[ids[i]].push_back(i); return cmps; } #undef CUT #line 5 "src/graph/DMDecomp.hpp" vector, vector>> dm_decomp(int lsiz, int rsiz, vector> match, vector> edges) { vector tor(lsiz, -1), tol(rsiz, -1); for (auto &[i, j] : match) { tor[i] = j; tol[j] = i; } vector> g(lsiz), h(rsiz); for (auto &[i, j] : edges) { g[i].push_back(j); h[j].push_back(i); } vector wk_l(lsiz, false), wk_r(rsiz, false); auto dfs_l = [&](auto dfs_l, int i) -> void { if (i == -1 or exchange(wk_l[i], true)) return; for (int j : g[i]) wk_r[j] = true, dfs_l(dfs_l, tol[j]); }; rep(i, 0, lsiz) if (tor[i] == -1) dfs_l(dfs_l, i); vector w0_l(lsiz, false), w0_r(rsiz, false); auto dfs_r = [&](auto dfs_r, int j) -> void { if (j == -1 or exchange(w0_r[j], true)) return; for (int i : h[j]) w0_l[i] = true, dfs_r(dfs_r, tor[i]); }; rep(j, 0, rsiz) if (tol[j] == -1) dfs_r(dfs_r, j); vector, vector>> dm; auto add = [&](int i, int j) { auto& [l, r] = dm.back(); l.push_back(i), r.push_back(j); }; // W_0 dm.emplace_back(); rep(i, 0, lsiz) if (w0_l[i]) { add(i, tor[i]); } rep(j, 0, rsiz) if (w0_r[j] and tol[j] == -1) { dm.back().second.push_back(j); } // W_1, ..., W_{k-1} vector> scc_g(lsiz + rsiz); for (int i = 0; i < lsiz; ++i) { for (int j : g[i]) scc_g[i].push_back(lsiz + j); int j = tor[i]; if (j != -1) scc_g[lsiz + j].push_back(i); } for (const auto& group : scc(scc_g)) { if (int v0 = group.front(); v0 < lsiz) { if (w0_l[v0] or wk_l[v0]) continue; } else { v0 -= lsiz; if (w0_r[v0] or wk_r[v0]) continue; } dm.emplace_back(); for (int i : group) if (i < lsiz) add(i, tor[i]); } // W_k dm.emplace_back(); rep(j, 0, rsiz) if (wk_r[j]) { add(tol[j], j); } rep(i, 0, lsiz) if (wk_l[i] and tor[i] == -1) { dm.back().first.push_back(i); } return dm; } #undef CUT #line 5 "test/graph/dm/yuki1745.test.cpp" int main() { int n, m, l; read(n, m, l); vector> edges; vector> g(n + m); for (int i = 0; i < l; ++i) { int u, v; cin >> u >> v; --u, --v; g[u].push_back(n + v); g[n + v].push_back(u); edges.emplace_back(u, v); } vector matched = bipartite_matching(g); vector> match; rep(i, 0, n) { if (matched[i] != -1) { match.emplace_back(i, matched[i] - n); } } auto dm = dm_decomp(n, m, match, edges); const int k = dm.size() - 1; vector cl(n), cr(m); for (int i = 0; i <= k; ++i) { for (int u : dm[i].first) cl[u] = i; for (int v : dm[i].second) cr[v] = i; } for (const auto& [u, v] : edges) { if (cl[u] != cr[v]) { std::cout << "No\n"; } else { std::cout << "Yes\n"; } } return 0; }