change bit_width(x + 0u) - 1 to bit_width(x / 2u)

Author: lrvideckis

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

@@ -23,7 +23,7 @@ template<class T, class F> struct RMQ {
   }
   T query(int l, int r) {
     assert(l < r);
-    int lg = bit_width(r - l + 0u) - 1;
+    int lg = bit_width((r - l) / 2u);
     return op(dp[lg][l], dp[lg][r - (1 << lg)]);
   }
 };

library/data_structures_[l,r)/seg_tree_uncommon/max_right.hpp

@@ -1,7 +1,6 @@
 int max_right(int l, int r, auto f) {
   for (T x = unit; l < r;) {
-    int u = l + n,
-        v = bit_width(min(u & -u, r - l) + 0u) - 1,
+    int u = l + n, v = bit_width(min(u & -u, r - l) / 2u),
         m = l + (1 << v);
     if (T y = op(x, s[u >> v]); f(m, y)) l = m, x = y;
     else r = m - 1;

library/data_structures_[l,r)/seg_tree_uncommon/min_left.hpp

@@ -1,7 +1,6 @@
 int min_left(int l, int r, auto f) {
   for (T x = unit; l < r;) {
-    int u = r + n,
-        v = bit_width(min(u & -u, r - l) + 0u) - 1,
+    int u = r + n, v = bit_width(min(u & -u, r - l) / 2u),
         m = r - (1 << v);
     if (T y = op(s[(u - 1) >> v], x); f(m, y))
       r = m, x = y;

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

@@ -27,7 +27,7 @@ template<class T, class F> struct disjoint_rmq {
   }
   T query(int l, int r) {
     if (l == r) return dp[0][l];
-    int lg = bit_width((l ^ r) + 0u) - 1;
+    int lg = bit_width((l ^ r) / 2u);
     return op(dp[lg][l], dp[lg][r]);
   }
 };

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

@@ -23,7 +23,7 @@ template<class T, class F> struct RMQ {
   }
   T query(int l, int r) {
     assert(l <= r);
-    int lg = bit_width(r - l + 1u) - 1;
+    int lg = bit_width((r - l + 1) / 2u);
     return op(dp[lg][l], dp[lg][r - (1 << lg) + 1]);
   }
 };

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

@@ -19,8 +19,7 @@
 //! @time O(n + q log n)
 //! @space O(n)
 int nxt(int& l, int r) {
-  int u = l,
-      v = bit_width(min(l & -l, r - l + 1) + 0u) - 1;
+  int u = l, v = bit_width(min(l & -l, r - l + 1) / 2u);
   return l += 1 << v, u >> v;
 }
 template<class T, class F> struct tree {

library/data_structures_[l,r]/seg_tree_uncommon/max_right.hpp

@@ -2,7 +2,7 @@ int max_right(int l, int r, auto f) {
   if (T x = s[l + n]; f(l, x))
     for (l++; l <= r;) {
       int u = l + n,
-          v = bit_width(min(u & -u, r - l + 1) + 0u) - 1,
+          v = bit_width(min(u & -u, r - l + 1) / 2u),
           m = l + (1 << v) - 1;
       if (T y = op(x, s[u >> v]); f(m, y))
         l = m + 1, x = y;

library/data_structures_[l,r]/seg_tree_uncommon/min_left.hpp

@@ -2,7 +2,7 @@ int min_left(int l, int r, auto f) {
   if (T x = s[r + n]; f(r, x))
     for (r--; l <= r;) {
       int u = r + 1 + n,
-          v = bit_width(min(u & -u, r - l + 1) + 0u) - 1,
+          v = bit_width(min(u & -u, r - l + 1) / 2u),
           m = r - (1 << v) + 1;
       if (T y = op(s[(u - 1) >> v], x); f(m, y))
         r = m - 1, x = y;

library/dsu/range_parallel_dsu.hpp

@@ -9,7 +9,7 @@ struct rp_dsu {
   vector<DSU> dsus;
   rp_dsu(int n): dsus(bit_width(n + 0u), DSU(n)) {}
   void join(int u, int v, int len, auto f) {
-    int i = bit_width(len + 0u) - 1;
+    int i = bit_width(len / 2u);
     join(u, v, f, i);
     join(u + len - (1 << i), v + len - (1 << i), f, i);
   }

library/trees/uncommon/ladder_decomposition.hpp

@@ -45,7 +45,7 @@ struct ladder {
   int kth_par(int u, int k) {
     assert(0 <= k && k <= d[u]);
     if (k == 0) return u;
-    int bit = bit_width(k + 0u) - 1;
+    int bit = bit_width(k / 2u);
     u = jmp[bit][u], k -= (1 << bit);
     int i = idx[u], j = i + d[lad[i]] - d[u];
     assert(lad[j] == u);