fix

Author: lrvideckis

library/trees/subtree_isomorphism.hpp

@@ -8,21 +8,16 @@
 //!     isomorphic to subtree v
 //! @time O(n log n)
 //! @space O(n)
-struct subtree_iso {
-  int num_distinct_subtrees;
-  vi iso_id;
-  subtree_iso(const vector<vi>& adj): iso_id(sz(adj), -1) {
-    map<vi, int> hashes;
-    auto dfs = [&](auto&& self, int v, int p) -> int {
-      vi ch_ids;
-      for (int u : adj[v])
-        if (u != p) ch_ids.push_back(self(self, u, v));
-      ranges::sort(ch_ids);
-      return iso_id[v] =
-               hashes.try_emplace(ch_ids, sz(hashes))
-                 .first->second;
-    };
-    rep(i, 0, sz(adj)) if (iso_id[i] == -1) dfs(dfs, i, i);
-    num_distinct_subtrees = sz(hashes);
-  }
-};
+pair<int, vi> subtree_iso(const vector<vi>& adj) {
+  vi iso_id(sz(adj), -1);
+  map<vi, int> hashes;
+  auto dfs = [&](auto&& self, int v, int p) -> int {
+    vi ch_ids;
+    for (int u : adj[v])
+      if (u != p) ch_ids.push_back(self(self, u, v));
+    ranges::sort(ch_ids);
+    return iso_id[v] = hashes.try_emplace(ch_ids, sz(hashes)).first->second;
+  };
+  rep(i, 0, sz(adj)) if (iso_id[i] == -1) dfs(dfs, i, i);
+  return {sz(hashes), iso_id};
+}

tests/library_checker_aizu_tests/trees/subtree_isomorphism.test.cpp

@@ -1,5 +1,6 @@
 #define PROBLEM \
   "https://judge.yosupo.jp/problem/rooted_tree_isomorphism_classification"
+#undef _GLIBCXX_DEBUG
 #include "../template.hpp"
 #include "../../../library/trees/subtree_isomorphism.hpp"
 int main() {
@@ -18,11 +19,11 @@ int main() {
     adj_rooted[p].push_back(i);
   }
   auto [num_distinct_subtrees, iso_id] =
-    subtree_iso(adj_unrooted);
+      subtree_iso(adj_unrooted);
   auto [num_distinct_subtrees_rooted, iso_id_rooted] =
-    subtree_iso(adj_rooted);
+      subtree_iso(adj_rooted);
   assert(
-    num_distinct_subtrees == num_distinct_subtrees_rooted);
+      num_distinct_subtrees == num_distinct_subtrees_rooted);
   cout << num_distinct_subtrees << '\n';
   for (int i = 0; i < n; i++) {
     cout << iso_id[i] << " ";