Merge remote-tracking branch 'origin/dev' into use-ranges-algorithms

Author: cameroncuster

.verify-helper/timestamps.remote.json

@@ -49,9 +49,9 @@
 "tests/library_checker_aizu_tests/dsu/dsu_bipartite.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/dsu/dsu_weighted_aizu.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/dsu/dsu_weighted_lib_checker.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/dsu/kruskal_tree_aizu.test.cpp": "2026-07-07 09:17:02 -0700",
+"tests/library_checker_aizu_tests/dsu/kruskal_tree_aizu.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/dsu/line_tree_aizu.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/dsu/line_tree_lib_checker.test.cpp": "2026-07-06 13:10:16 -0700",
+"tests/library_checker_aizu_tests/dsu/line_tree_lib_checker.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/dsu/range_parallel_dsu.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/flow/hungarian.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/flow/min_cost_max_flow.test.cpp": "2026-04-06 14:41:55 -0600",
@@ -82,14 +82,14 @@
 "tests/library_checker_aizu_tests/handmade_tests/hilbert_mos.test.cpp": "2026-07-10 20:39:22 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/kd_bit.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/kth_par.test.cpp": "2026-07-10 20:39:22 -0700",
-"tests/library_checker_aizu_tests/handmade_tests/manacher.test.cpp": "2026-07-09 23:01:31 -0500",
+"tests/library_checker_aizu_tests/handmade_tests/manacher.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/merge_st_and_wavelet.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/mobius.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/mod_division.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/n_choose_k.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/permutation_tree_small.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/handmade_tests/rmq_small_n.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/handmade_tests/sa_find_subarray.test.cpp": "2026-07-09 23:01:31 -0500",
+"tests/library_checker_aizu_tests/handmade_tests/sa_find_subarray.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/seg_tree_find.test.cpp": "2026-07-10 20:39:22 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/seg_tree_find_small.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/seg_tree_midpoint.test.cpp": "2026-07-07 09:17:02 -0700",
@@ -116,20 +116,20 @@
 "tests/library_checker_aizu_tests/monotonic_stack_related/count_rectangles.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/monotonic_stack_related/max_rect_histogram.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/strings/kmp.test.cpp": "2026-07-08 09:28:48 -0700",
-"tests/library_checker_aizu_tests/strings/lcp_array.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/strings/lcp_query_palindrome.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/strings/lcp_query_zfunc.test.cpp": "2026-07-09 23:01:31 -0500",
+"tests/library_checker_aizu_tests/strings/lcp_array.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/lcp_query_palindrome.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/lcp_query_zfunc.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/strings/lcs_dp.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/strings/lcs_queries.test.cpp": "2026-07-10 20:39:22 -0700",
 "tests/library_checker_aizu_tests/strings/lcs_queries_merge_sort_tree.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/strings/manacher.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/strings/multi_matching_bs.test.cpp": "2026-07-09 23:01:31 -0500",
+"tests/library_checker_aizu_tests/strings/manacher.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/multi_matching_bs.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/strings/prefix_function.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/strings/sa_cmp.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/strings/sa_sort_pairs.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/strings/single_matching_bs.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/strings/suffix_array.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/strings/suffix_array_short.test.cpp": "2026-07-07 12:06:00 -0700",
+"tests/library_checker_aizu_tests/strings/sa_cmp.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/sa_sort_pairs.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/single_matching_bs.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/suffix_array.test.cpp": "2026-07-12 10:49:50 -0700",
+"tests/library_checker_aizu_tests/strings/suffix_array_short.test.cpp": "2026-07-12 10:49:50 -0700",
 "tests/library_checker_aizu_tests/strings/trie.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/strings/wildcard_pattern_matching.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/trees/cd_count_paths_per_length.test.cpp": "2026-07-08 09:28:48 -0700",

library/dsu/kruskal_tree.hpp

@@ -1,12 +1,13 @@
 #pragma once
 //! https://mzhang2021.github.io/cp-blog/kruskal/
+//! requires n >= 1 (2*n-1 allocation underflows when n == 0)
 //! @time O(n log n)
 //! @space O(n)
 struct kr_tree {
   int id;
   vi p;
   vector<vi> g;
-  kr_tree(int n): id(n), p(2 * n, -1), g(2 * n) {}
+  kr_tree(int n): id(n), p(2 * n - 1, -1), g(2 * n - 1) {}
   int f(int u) { return p[u] < 0 ? u : p[u] = f(p[u]); }
   bool join(int u, int v) {
     if ((u = f(u)) == (v = f(v))) return 0;

library/strings/manacher/manacher.hpp

@@ -14,6 +14,7 @@
 //! string b a a b a
 //! center  1 3 5 7
 //!
+//! requires n >= 1 (2*n-1 allocation underflows when n == 0)
 //! @time O(n)
 //! @space O(n)
 vi manacher(const auto& s) {

library/strings/suffix_array/suffix_array.hpp

@@ -32,6 +32,7 @@
 //!   auto [sa1, sa_inv1, lcp1] = get_sa(s_vec, 100'001);
 //! @endcode
 //!
+//! requires n >= 1 (lcp size n-1 underflows when n == 0)
 //! @time O(nlogn + max_num)
 //! @space O(n + max_num)
 auto get_sa(const auto& s, int max_num) {

library/strings/suffix_array/suffix_array_short.hpp

@@ -8,6 +8,7 @@
 //!   auto [sa1, sa_inv1, lcp1] = sa_short(s_vec);
 //! @endcode
 //! about 2-3x slower than KACTL
+//! requires n >= 1 (lcp size n-1 underflows when n == 0)
 //! @time O(n * log^2(n))
 //! @space O(n)
 auto sa_short(const auto& s) {