Add cuts callback (#135)

lrvideckis · web-flow · web-flow · commit 91669382989b · 2025-06-23T03:43:10.000-06:00
* add cuts with callback * [auto-verifier] verify commit ebabb1b * golf and format * [auto-verifier] verify commit de0d02e * golf * [auto-verifier] verify commit 899e5be * update * [auto-verifier] verify commit 4fd3c4d * update config * golf * [auto-verifier] verify commit 422f8e5 * fix bug in script * name script after the commands it runs * format tests now * [auto-verifier] verify commit 023a617 * catch typo * simplify * reorder functions * ignore these again * fix typo * [auto-verifier] verify commit f90e8d6 * fix comment example init * fix docs again * [auto-verifier] verify commit 0a5a61f --------- Co-authored-by: GitHub <noreply@github.com>
diff --git a/.github/workflows/programming_team_code_ci.yml b/.github/workflows/programming_team_code_ci.yml
@@ -29,7 +29,7 @@ jobs:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       run: oj-verify all --tle 60 --timeout 21600
 
-  check_format_lint:
+  greps_clangformat_cppcheck:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
@@ -41,7 +41,7 @@ jobs:
     - name: Install dependencies
       run: sudo apt update && sudo apt install -y clang-format-19 cppcheck
     - name: checks format then lints
-      run: make --directory=tests/ check_format_lint
+      run: make --directory=tests/ greps_clangformat_cppcheck
 
   clangtidy:
     runs-on: ubuntu-latest
@@ -101,7 +101,7 @@ jobs:
 
   publish_ptc:
     runs-on: ubuntu-latest
-    needs: [library_checker_aizu, check_format_lint, clangtidy, compile_gcc, compile_clang, files_without_tests, build_ptc]
+    needs: [library_checker_aizu, greps_clangformat_cppcheck, clangtidy, compile_gcc, compile_clang, files_without_tests, build_ptc]
     if: github.ref == 'refs/heads/dev' && github.event_name == 'push'
     steps:
     - uses: actions/checkout@v2
@@ -119,7 +119,7 @@ jobs:
 
   update_main:
     runs-on: ubuntu-latest
-    needs: [library_checker_aizu, check_format_lint, clangtidy, compile_gcc, compile_clang, files_without_tests]
+    needs: [library_checker_aizu, greps_clangformat_cppcheck, clangtidy, compile_gcc, compile_clang, files_without_tests]
     if: github.ref == 'refs/heads/dev' && github.event_name == 'push'
     steps:
     - uses: actions/checkout@v2
diff --git a/.verify-helper/timestamps.remote.json b/.verify-helper/timestamps.remote.json
@@ -10,9 +10,9 @@
 "tests/library_checker_aizu_tests/data_structures/bit_rupq.test.cpp": "2024-12-05 10:41:42 -0600",
 "tests/library_checker_aizu_tests/data_structures/bit_rurq.test.cpp": "2024-12-05 10:41:42 -0600",
 "tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp": "2024-12-14 19:50:29 -0600",
-"tests/library_checker_aizu_tests/data_structures/deque.test.cpp": "2024-12-14 15:47:13 -0600",
-"tests/library_checker_aizu_tests/data_structures/deque_op.test.cpp": "2024-12-14 19:50:29 -0600",
-"tests/library_checker_aizu_tests/data_structures/deque_sliding_window.test.cpp": "2024-12-14 15:47:13 -0600",
+"tests/library_checker_aizu_tests/data_structures/deque.test.cpp": "2025-06-23 03:31:40 -0600",
+"tests/library_checker_aizu_tests/data_structures/deque_op.test.cpp": "2025-06-23 03:31:40 -0600",
+"tests/library_checker_aizu_tests/data_structures/deque_sliding_window.test.cpp": "2025-06-23 03:31:40 -0600",
 "tests/library_checker_aizu_tests/data_structures/disjoint_rmq_inc.test.cpp": "2024-12-14 15:47:13 -0600",
 "tests/library_checker_aizu_tests/data_structures/disjoint_rmq_inc_lines.test.cpp": "2024-12-14 15:47:13 -0600",
 "tests/library_checker_aizu_tests/data_structures/disjoint_rmq_lines.test.cpp": "2024-12-14 15:47:13 -0600",
@@ -52,6 +52,7 @@
 "tests/library_checker_aizu_tests/flow/min_cost_max_flow.test.cpp": "2024-12-05 10:41:42 -0600",
 "tests/library_checker_aizu_tests/graphs/biconnected_components.test.cpp": "2025-02-10 23:30:47 -0700",
 "tests/library_checker_aizu_tests/graphs/connected_components_of_complement_graph.test.cpp": "2024-12-14 19:50:29 -0600",
+"tests/library_checker_aizu_tests/graphs/cuts_callback.test.cpp": "2025-06-23 03:38:41 -0600",
 "tests/library_checker_aizu_tests/graphs/dijkstra_aizu.test.cpp": "2024-12-14 19:50:29 -0600",
 "tests/library_checker_aizu_tests/graphs/dijkstra_lib_checker.test.cpp": "2024-12-14 19:50:29 -0600",
 "tests/library_checker_aizu_tests/graphs/directed_cycle.test.cpp": "2025-02-10 23:30:47 -0700",
diff --git a/library/data_structures/deque_op/back.hpp b/library/data_structures/deque_op/back.hpp
diff --git a/library/data_structures/deque_op/front.hpp b/library/data_structures/deque_op/front.hpp
diff --git a/library/data_structures/deque_op/queue_only.hpp b/library/data_structures/deque_op/queue_only.hpp
@@ -18,10 +18,8 @@ template<class T, class F> struct deq {
     return op(l.back()[1], r.back()[1]);
   }
   int siz() { return sz(l) + sz(r); }
-  void push_back(T elem) {
-    r.push_back(
-      {elem, empty(r) ? elem : op(r.back()[1], elem)});
-  }
+  T front() { return (empty(l) ? r[0] : l.back())[0]; }
+  T back() { return (empty(r) ? l[0] : r.back())[0]; }
   void pop_front() {
     if (empty(l)) {
       vector<T> a(sz(r));
@@ -31,6 +29,10 @@ template<class T, class F> struct deq {
     }
     l.pop_back();
   }
+  void push_back(T elem) {
+    r.push_back(
+      {elem, empty(r) ? elem : op(r.back()[1], elem)});
+  }
   void rebuild(const vector<T>& a, int sz_le) {
     vector<T> presum(sz(a));
     partial_sum(rend(a) - sz_le, rend(a),
@@ -46,6 +48,4 @@ template<class T, class F> struct deq {
   }
 #include "deque.hpp"
 #include "index.hpp"
-#include "front.hpp"
-#include "back.hpp"
 };
diff --git a/library/graphs/bridges_cuts/cuts_callback.hpp b/library/graphs/bridges_cuts/cuts_callback.hpp
@@ -0,0 +1,40 @@
+#pragma once
+//! https://cp-algorithms.com/graph/cutpoints.html
+//! @code
+//!   {
+//!     vector<vector<int>> adj(n);
+//!     cuts_callback(adj, [&](const vi& nodes) {});
+//!   }
+//!   vector<basic_string<int>> adj(n);
+//!   rep (i, 0, m) {
+//!     int u, v;
+//!     cin >> u >> v;
+//!     u--, v--;
+//!     adj[u] += v;
+//!     adj[v] += u;
+//!   }
+//!   cuts_callback(adj, [&](const vi& nodes) {
+//!   });
+//! @endcode
+//! @time O(n + m)
+//! @space O(n + m)
+void cuts_callback(const auto& adj, auto f) {
+  int n = sz(adj), q = 0, s = 0;
+  vi tin(n), st(n);
+  auto dfs = [&](auto&& self, int v, int p) -> int {
+    int low = tin[v] = ++q;
+    for (int u : adj[v])
+      if (u != p) {
+        int siz = s, lu = 0;
+        low = min(low,
+          tin[u] ?: (lu = self(self, st[s++] = u, v)));
+        if (lu >= tin[v]) {
+          st[s++] = v;
+          f(vi(siz + all(st) - n + s));
+          s = siz;
+        }
+      }
+    return low;
+  };
+  rep(i, 0, n) if (!tin[i]) dfs(dfs, i, i);
+}
diff --git a/tests/.config/.code_snippet_excluded_file_list b/tests/.config/.code_snippet_excluded_file_list
@@ -7,9 +7,7 @@ find_first.hpp
 find_last.hpp
 loops
 kth_path.hpp
-back.hpp
 deque.hpp
-front.hpp
 index.hpp
 compare_substrings.hpp
 compare_suffixes.hpp
diff --git a/tests/Makefile b/tests/Makefile
@@ -7,7 +7,7 @@ help:
 	@echo "                                     |"
 	@echo "make compile_commented_snippets      | compile code in @code...@endcode comments"
 	@echo "                                     |"
-	@echo "make check_format_lint               | checks format with clang-format, then cppcheck"
+	@echo "make greps_clangformat_cppcheck      | greps to catch various bad things, clang-format, cppcheck"
 	@echo "                                     |"
 	@echo "make do_format                       | format with clang-format"
 	@echo "                                     |"
@@ -31,8 +31,8 @@ compile_gcc:
 compile_clang:
 	./scripts/compile_clang.sh
 
-check_format_lint:
-	./scripts/check_format_lint.sh
+greps_clangformat_cppcheck:
+	./scripts/greps_clangformat_cppcheck.sh
 
 do_format:
 	./scripts/do_format.sh
diff --git a/tests/library_checker_aizu_tests/graphs/cuts_callback.test.cpp b/tests/library_checker_aizu_tests/graphs/cuts_callback.test.cpp
@@ -0,0 +1,32 @@
+#define PROBLEM \
+  "https://judge.yosupo.jp/problem/biconnected_components"
+#include "../template.hpp"
+#include "../../../library/graphs/bridges_cuts/cuts_callback.hpp"
+int main() {
+  cin.tie(0)->sync_with_stdio(0);
+  int n, m;
+  cin >> n >> m;
+  vector<basic_string<int>> adj(n);
+  for (int i = 0; i < n; i++) adj[i] += i;
+  for (int i = 0; i < m; i++) {
+    int u, v;
+    cin >> u >> v;
+    adj[u] += v;
+    adj[v] += u;
+  }
+  vector<bool> vis(n, 0);
+  vector<vector<int>> all_bccs;
+  cuts_callback(adj, [&](const vi& nodes_bcc) {
+    for (int v : nodes_bcc) vis[v] = 1;
+    all_bccs.push_back(nodes_bcc);
+  });
+  for (int i = 0; i < n; i++)
+    if (!vis[i]) all_bccs.push_back({i});
+  cout << ssize(all_bccs) << '\n';
+  for (const vector<int>& other_nodes : all_bccs) {
+    cout << ssize(other_nodes) << ' ';
+    for (int v : other_nodes) cout << v << ' ';
+    cout << '\n';
+  }
+  return 0;
+}
diff --git a/tests/scripts/greps_clangformat_cppcheck.sh b/tests/scripts/greps_clangformat_cppcheck.sh
@@ -36,7 +36,7 @@ find ../library/ library_checker_aizu_tests/ -name "*[A-Z]*" -or -name "*-*" |
 	grep --invert-match "README" &&
 	exit 1
 
-clang-format-19 --dry-run --Werror --style=file:.config/.clang-format library_checker_aizu_tests/**/*.hpp ../library/**/*.hpp ../library/**/*.cpp || exit 1
+clang-format-19 --dry-run --Werror --style=file:.config/.clang-format library_checker_aizu_tests/**/*.hpp library_checker_aizu_tests/**/*.test.cpp ../library/**/*.hpp ../library/**/*.cpp || exit 1
 
 git submodule init
 git submodule update
