use >> 1 for bit manipulation, / 2 for arithmetic halving

.verify-helper/timestamps.remote.json

@@ -1,21 +1,21 @@
 {
 "tests/library_checker_aizu_tests/convolution/gcd_convolution.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/convolution/lcm_convolution.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/convolution/min_plus_convolution.test.cpp": "2026-07-08 09:28:48 -0700",
+"tests/library_checker_aizu_tests/convolution/min_plus_convolution.test.cpp": "2026-07-10 19:12:24 -0700",
 "tests/library_checker_aizu_tests/convolution/xor_convolution.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/data_structures/binary_search_example.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/data_structures/binary_trie.test.cpp": "2026-07-08 09:28:48 -0700",
-"tests/library_checker_aizu_tests/data_structures/bit.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/bit_inc.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/bit_inc_walk.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/bit_ordered_set.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/bit_rupq.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/bit_rurq.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/data_structures/deque.test.cpp": "2026-07-06 13:49:19 -0700",
-"tests/library_checker_aizu_tests/data_structures/deque_index.test.cpp": "2026-07-06 13:49:19 -0700",
-"tests/library_checker_aizu_tests/data_structures/deque_op.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/data_structures/deque_sliding_window.test.cpp": "2026-07-06 13:49:19 -0700",
+"tests/library_checker_aizu_tests/data_structures/binary_trie.test.cpp": "2026-07-10 19:12:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit_inc.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit_inc_walk.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit_ordered_set.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit_rupq.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit_rurq.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/deque.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/deque_index.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/deque_op.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/deque_sliding_window.test.cpp": "2026-07-10 16:56:24 -0700",
 "tests/library_checker_aizu_tests/data_structures/disjoint_rmq_inc.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/data_structures/disjoint_rmq_inc_lines.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/data_structures/disjoint_rmq_inc_sum.test.cpp": "2026-07-09 23:01:31 -0500",
@@ -24,11 +24,11 @@
 "tests/library_checker_aizu_tests/data_structures/kd_bit_1d.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/data_structures/kth_smallest_pst.test.cpp": "2026-07-07 10:02:09 -0700",
 "tests/library_checker_aizu_tests/data_structures/kth_smallest_wavelet_matrix.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree_constructor.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree_inc.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree_inc_constructor.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/data_structures/merge_sort_tree.test.cpp": "2026-07-06 13:10:16 -0700",
+"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree_constructor.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree_inc.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/lazy_segment_tree_inc_constructor.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/merge_sort_tree.test.cpp": "2026-07-10 16:56:24 -0700",
 "tests/library_checker_aizu_tests/data_structures/mode_query.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/data_structures/permutation_tree.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/data_structures/persistent_queue_tree.test.cpp": "2026-07-07 10:02:09 -0700",
@@ -37,14 +37,14 @@
 "tests/library_checker_aizu_tests/data_structures/rmq_linear.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/data_structures/rmq_sparse_table.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/data_structures/rmq_sparse_table_inc.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_inc.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_inc_line.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_inc_queue.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_inc_walk.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_line.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_queue.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/data_structures/simple_tree_walk.test.cpp": "2026-07-09 23:01:31 -0500",
+"tests/library_checker_aizu_tests/data_structures/simple_tree.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_inc.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_inc_line.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_inc_queue.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_inc_walk.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_line.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_queue.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/data_structures/simple_tree_walk.test.cpp": "2026-07-10 16:56:24 -0700",
 "tests/library_checker_aizu_tests/dsu/dsu.test.cpp": "2026-02-27 15:26:53 -0700",
 "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",
@@ -79,27 +79,27 @@
 "tests/library_checker_aizu_tests/handmade_tests/edge_cd_small_trees.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/fib_matrix_expo.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/functional_graph.test.cpp": "2026-07-07 12:06:00 -0700",
-"tests/library_checker_aizu_tests/handmade_tests/hilbert_mos.test.cpp": "2026-07-07 12:06:00 -0700",
+"tests/library_checker_aizu_tests/handmade_tests/hilbert_mos.test.cpp": "2026-07-10 16:56:24 -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": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/handmade_tests/manacher.test.cpp": "2026-07-09 23:01:31 -0500",
-"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/kth_par.test.cpp": "2026-07-10 19:12:24 -0700",
+"tests/library_checker_aizu_tests/handmade_tests/manacher.test.cpp": "2026-07-10 19:12:24 -0700",
+"tests/library_checker_aizu_tests/handmade_tests/merge_st_and_wavelet.test.cpp": "2026-07-10 16:56:24 -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/seg_tree_find.test.cpp": "2026-07-09 22:46:18 -0600",
-"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",
+"tests/library_checker_aizu_tests/handmade_tests/seg_tree_find.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/handmade_tests/seg_tree_find_small.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/handmade_tests/seg_tree_midpoint.test.cpp": "2026-07-10 16:56:24 -0700",
 "tests/library_checker_aizu_tests/handmade_tests/xor_basis_walk.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/loops/chooses.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/loops/quotients.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/loops/submasks.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/loops/supermasks.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/math/binary_matrix_mult.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/math/count_paths.test.cpp": "2026-07-07 21:14:10 -0700",
+"tests/library_checker_aizu_tests/math/count_paths.test.cpp": "2026-07-10 19:12:24 -0700",
 "tests/library_checker_aizu_tests/math/derangement.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/math/matrix_determinant.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/math/matrix_mult.test.cpp": "2026-07-06 13:10:16 -0700",
@@ -108,7 +108,7 @@
 "tests/library_checker_aizu_tests/math/partitions.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/math/prime_sieve.test.cpp": "2026-07-06 13:10:16 -0700",
 "tests/library_checker_aizu_tests/math/solve_linear_mod.test.cpp": "2026-07-08 09:28:48 -0700",
-"tests/library_checker_aizu_tests/math/tetration.test.cpp": "2026-07-06 10:41:44 -0700",
+"tests/library_checker_aizu_tests/math/tetration.test.cpp": "2026-07-10 19:12:24 -0700",
 "tests/library_checker_aizu_tests/math/totient.test.cpp": "2024-11-17 14:04:03 -0600",
 "tests/library_checker_aizu_tests/math/xor_basis_intersection.test.cpp": "2026-07-07 12:06:00 -0700",
 "tests/library_checker_aizu_tests/monotonic_stack_related/cartesian_binary_tree.test.cpp": "2026-07-07 12:06:00 -0700",
@@ -120,9 +120,9 @@
 "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/lcs_dp.test.cpp": "2026-07-06 13:10:16 -0700",
-"tests/library_checker_aizu_tests/strings/lcs_queries.test.cpp": "2026-07-09 22:46:18 -0600",
-"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/lcs_queries.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/strings/lcs_queries_merge_sort_tree.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/strings/manacher.test.cpp": "2026-07-10 19:12:24 -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/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",
@@ -133,18 +133,18 @@
 "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",
-"tests/library_checker_aizu_tests/trees/edge_cd_contour_range_query.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/trees/edge_cd_contour_range_update.test.cpp": "2026-07-09 22:46:18 -0600",
+"tests/library_checker_aizu_tests/trees/edge_cd_contour_range_query.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/trees/edge_cd_contour_range_update.test.cpp": "2026-07-10 16:56:24 -0700",
 "tests/library_checker_aizu_tests/trees/edge_cd_count_paths_per_length.test.cpp": "2026-07-08 09:28:48 -0700",
 "tests/library_checker_aizu_tests/trees/edge_cd_reroot_dp.test.cpp": "2026-07-08 09:28:48 -0700",
-"tests/library_checker_aizu_tests/trees/hld_aizu1.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/trees/hld_aizu2.test.cpp": "2026-07-08 22:13:09 -0500",
-"tests/library_checker_aizu_tests/trees/hld_lib_checker_path.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/trees/hld_lib_checker_subtree_edges.test.cpp": "2026-07-09 22:46:18 -0600",
-"tests/library_checker_aizu_tests/trees/hld_lib_checker_subtree_nodes.test.cpp": "2026-07-09 22:46:18 -0600",
+"tests/library_checker_aizu_tests/trees/hld_aizu1.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/trees/hld_aizu2.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/trees/hld_lib_checker_path.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/trees/hld_lib_checker_subtree_edges.test.cpp": "2026-07-10 16:56:24 -0700",
+"tests/library_checker_aizu_tests/trees/hld_lib_checker_subtree_nodes.test.cpp": "2026-07-10 16:56:24 -0700",
 "tests/library_checker_aizu_tests/trees/kth_path_hagerup.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/trees/kth_path_ladder.test.cpp": "2026-07-09 23:01:31 -0500",
-"tests/library_checker_aizu_tests/trees/kth_path_linear.test.cpp": "2026-07-09 23:01:31 -0500",
+"tests/library_checker_aizu_tests/trees/kth_path_linear.test.cpp": "2026-07-10 19:12:24 -0700",
 "tests/library_checker_aizu_tests/trees/kth_path_tree_lift.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/trees/lca_all_methods_aizu.test.cpp": "2026-07-09 23:01:31 -0500",
 "tests/library_checker_aizu_tests/trees/lca_all_methods_lib_checker.test.cpp": "2026-07-09 23:01:31 -0500",

library/data_structures_[l,r)/bit_uncommon/walk.hpp

@@ -1,7 +1,7 @@
 int walk(ll sum) {
   if (sum <= 0) return -1;
   int r = 0;
-  for (int i = bit_floor(size(s)); i; i /= 2)
+  for (int i = bit_floor(size(s)); i; i >>= 1)
     if (r + i <= sz(s) && s[r + i - 1] < sum)
       sum -= s[(r += i) - 1];
   return r;

library/data_structures_[l,r)/seg_tree.hpp

@@ -27,12 +27,12 @@ template<class T, class F> struct tree {
   tree(int n, T unit, F op):
     n(n), unit(unit), op(op), s(2 * n, unit) {}
   void update(int i, T val) {
-    for (s[i += n] = val; i /= 2;)
+    for (s[i += n] = val; i >>= 1;)
       s[i] = op(s[2 * i], s[2 * i + 1]);
   }
   T query(int l, int r) {
     T x = unit, y = unit;
-    for (l += n, r += n; l < r; l /= 2, r /= 2) {
+    for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
       if (l % 2) x = op(x, s[l++]);
       if (r % 2) y = op(s[--r], y);
     }

library/data_structures_[l,r)/uncommon/hilbert_mos.hpp

@@ -11,7 +11,7 @@
 ll hilbert(int x, int y) {
   ll d = 0, mx = 1;
   while (mx <= max(x, y)) mx *= 4;
-  for (int s = mx / 2; s; s /= 2) {
+  for (int s = mx >> 1; s; s >>= 1) {
     bool rx = x & s, ry = y & s;
     d = d * 4 | (ry * 3 ^ rx);
     if (!rx) {

library/data_structures_[l,r]/seg_tree.hpp

@@ -30,7 +30,7 @@ template<class T, class F> struct tree {
     n(n), op(op), s(2 * n, unit) {}
 #include "seg_tree_uncommon/init.hpp"
   void update(int i, T val) {
-    for (s[i += n] = val; i /= 2;)
+    for (s[i += n] = val; i >>= 1;)
       s[i] = op(s[2 * i], s[2 * i + 1]);
   }
   T query(int l, int r) {

library/math/tetration_mod.hpp

@@ -13,7 +13,7 @@
 ll bin_exp(ll b, ll e, int mod) {
   ll res = 1;
   if ((b %= mod) < 0) b += mod;
-  for (; e; b = b * b % mod, e /= 2)
+  for (; e; b = b * b % mod, e >>= 1)
     if (e & 1) res = res * b % mod;
   return res;
 }

library/strings/binary_trie.hpp

@@ -18,7 +18,7 @@ struct binary_trie {
   binary_trie(): t(1) {}
   void update(ll num, int delta) {
     int v = 0;
-    for (ll bit = mx_bit; bit; bit /= 2) {
+    for (ll bit = mx_bit; bit; bit >>= 1) {
       bool b = num & bit;
       if (t[v].nxt[b] == -1) {
         t[v].nxt[b] = sz(t);
@@ -31,7 +31,7 @@ struct binary_trie {
   ll walk(ll num) {
     int v = 0;
     ll res = 0;
-    for (ll bit = mx_bit; bit; bit /= 2) {
+    for (ll bit = mx_bit; bit; bit >>= 1) {
       bool b = num & bit;
       int u = t[v].nxt[b];
       if (u != -1 && t[u].siz > 0) v = u, res |= num & bit;

library/trees/uncommon/linear_kth_par.hpp

@@ -50,7 +50,7 @@ struct linear_kth_par {
     assert(0 <= k && k <= d[u]);
     if (k == 0) return u;
     int anc_d = d[u] - k, bc = bit_ceil(k + 0u);
-    int t = (tin[u] + bc / 2) & -bc;
+    int t = (tin[u] + (bc >> 1)) & -bc;
     int i =
       idx[jmp[t].at(bit_width((d_tour[t] - anc_d) / 2u))];
     return lad[i + d[lad[i]] - anc_d];

tests/library_checker_aizu_tests/math/count_paths.test.cpp

@@ -13,7 +13,7 @@
 #undef modpow
 ll modpow(ll b, ll e) {
   ll res = 1;
-  for (; e; b = b * b % 998'244'353, e /= 2)
+  for (; e; b = b * b % 998'244'353, e >>= 1)
     if (e & 1) res = res * b % 998'244'353;
   return res;
 }