diff --git a/library/data_structures_[l,r)/bit.hpp b/library/data_structures_[l,r)/bit.hpp
index 3024a16f..1e3bf04a 100644
--- a/library/data_structures_[l,r)/bit.hpp
+++ b/library/data_structures_[l,r)/bit.hpp
@@ -1,10 +1,7 @@
 #pragma once
 //! @code
 //!   BIT bit(n);
-//!   bit.walk([&](int r, int64_t sum) -> bool {
-//!     // sum = a[0] + a[1] + ... + a[r - 1]
-//!   });
-//!   int r = bit.walk2(sum);
+//!   int r = bit.walk(sum);
 //!   // Returns min r s.t. sum of [0,r+1) >= sum
 //!   // Returns n if sum of [0,n) < sum
 //!   // Returns -1 if sum <= 0
@@ -25,6 +22,5 @@ struct BIT {
     return res;
   }
   ll query(int l, int r) { return query(r) - query(l); }
-#include "bit_uncommon/walk_lambda.hpp"
 #include "bit_uncommon/walk.hpp"
 };
diff --git a/library/data_structures_[l,r)/bit_uncommon/walk.hpp b/library/data_structures_[l,r)/bit_uncommon/walk.hpp
index 20c3a732..40ce10d7 100644
--- a/library/data_structures_[l,r)/bit_uncommon/walk.hpp
+++ b/library/data_structures_[l,r)/bit_uncommon/walk.hpp
@@ -1,4 +1,4 @@
-int walk2(ll sum) {
+int walk(ll sum) {
   if (sum <= 0) return -1;
   int r = 0;
   for (int i = bit_floor(size(s)); i; i /= 2)
diff --git a/library/data_structures_[l,r)/bit_uncommon/walk_lambda.hpp b/library/data_structures_[l,r)/bit_uncommon/walk_lambda.hpp
deleted file mode 100644
index fe55e883..00000000
--- a/library/data_structures_[l,r)/bit_uncommon/walk_lambda.hpp
+++ /dev/null
@@ -1,6 +0,0 @@
-void walk(auto f) {
-  ll sum = 0;
-  for (int i = bit_floor(size(s)), r = 0; i; i /= 2)
-    if (r + i <= sz(s) && f(r + i, sum + s[r + i - 1]))
-      sum += s[(r += i) - 1];
-}
diff --git a/library/data_structures_[l,r]/bit.hpp b/library/data_structures_[l,r]/bit.hpp
index e720d7ce..1c96c37f 100644
--- a/library/data_structures_[l,r]/bit.hpp
+++ b/library/data_structures_[l,r]/bit.hpp
@@ -1,10 +1,7 @@
 #pragma once
 //! @code
 //!   BIT bit(n);
-//!   bit.walk([&](int r, int64_t sum) -> bool {
-//!     // sum = a[0] + a[1] + ... + a[r]
-//!   });
-//!   int r = bit.walk2(sum);
+//!   int r = bit.walk(sum);
 //!   // Returns min r s.t. sum of [0,r] >= sum
 //!   // Returns n if sum of [0,n-1] < sum
 //!   // Returns -1 if sum <= 0
@@ -27,6 +24,5 @@ struct BIT {
   ll query(int l, int r) {
     return query(r) - query(l - 1);
   }
-#include "bit_uncommon/walk_lambda.hpp"
 #include "../data_structures_[l,r)/bit_uncommon/walk.hpp"
 };
diff --git a/library/data_structures_[l,r]/bit_uncommon/walk_lambda.hpp b/library/data_structures_[l,r]/bit_uncommon/walk_lambda.hpp
deleted file mode 100644
index 1f456b64..00000000
--- a/library/data_structures_[l,r]/bit_uncommon/walk_lambda.hpp
+++ /dev/null
@@ -1,6 +0,0 @@
-void walk(auto f) {
-  ll sum = 0;
-  for (int i = bit_floor(size(s)), r = 0; i; i /= 2)
-    if (r + i <= sz(s) && f(r + i - 1, sum + s[r + i - 1]))
-      sum += s[(r += i) - 1];
-}
diff --git a/tests/.config/.cppcheck_suppression_list b/tests/.config/.cppcheck_suppression_list
index 8a142f3b..49d1b2cf 100644
--- a/tests/.config/.cppcheck_suppression_list
+++ b/tests/.config/.cppcheck_suppression_list
@@ -60,5 +60,5 @@ unusedFunction:../kactl/content/data-structures/UnionFind.h:14
 unusedFunction:../kactl/content/number-theory/ModPow.h:13
 unusedFunction:../kactl/stress-tests/utilities/genTree.h:49
 containerOutOfBounds:../library/data_structures_[l,r)/uncommon/permutation_tree.hpp:85
-ctuOneDefinitionRuleViolation:../library/data_structures_[l,r)/bit.hpp:15
+ctuOneDefinitionRuleViolation:../library/data_structures_[l,r)/bit.hpp:12
 ctuOneDefinitionRuleViolation:../library/data_structures_[l,r)/lazy_seg_tree.hpp:4
diff --git a/tests/library_checker_aizu_tests/data_structures/bit.test.cpp b/tests/library_checker_aizu_tests/data_structures/bit.test.cpp
index 987d9400..32d1713c 100644
--- a/tests/library_checker_aizu_tests/data_structures/bit.test.cpp
+++ b/tests/library_checker_aizu_tests/data_structures/bit.test.cpp
@@ -58,7 +58,7 @@ int main() {
       }
       return 1;
     };
-    assert(bit.walk2(sum) == st.find_first(0, n, f));
+    assert(bit.walk(sum) == st.find_first(0, n, f));
   }
   return 0;
 }
diff --git a/tests/library_checker_aizu_tests/data_structures/bit_inc_walk.test.cpp b/tests/library_checker_aizu_tests/data_structures/bit_inc_walk.test.cpp
index 71709b07..4d072cca 100644
--- a/tests/library_checker_aizu_tests/data_structures/bit_inc_walk.test.cpp
+++ b/tests/library_checker_aizu_tests/data_structures/bit_inc_walk.test.cpp
@@ -23,27 +23,13 @@ int main() {
       if (bit.query(k, n - 1) == 0) cout << -1 << '\n';
       else {
         ll order = bit.query(k - 1);
-        int res = -1;
-        bit.walk([&](int r, ll sum) {
-          if (sum <= order) return 1;
-          res = r;
-          return 0;
-        });
-        cout << res << '\n';
+        cout << bit.walk(order + 1) << '\n';
       }
     } else {
       if (bit.query(k) == 0) cout << -1 << '\n';
       else {
         ll order = bit.query(k);
-        int res = -1;
-        bit.walk([&](int r, ll sum) {
-          if (sum >= order) {
-            res = r;
-            return 0;
-          }
-          return 1;
-        });
-        cout << res << '\n';
+        cout << bit.walk(order) << '\n';
       }
     }
   }
diff --git a/tests/library_checker_aizu_tests/data_structures/bit_ordered_set.test.cpp b/tests/library_checker_aizu_tests/data_structures/bit_ordered_set.test.cpp
index 009a8353..cf43717e 100644
--- a/tests/library_checker_aizu_tests/data_structures/bit_ordered_set.test.cpp
+++ b/tests/library_checker_aizu_tests/data_structures/bit_ordered_set.test.cpp
@@ -40,7 +40,7 @@ int main() {
       x = get_compressed_idx(x);
       if (bit.query(x, x) == 1) bit.update(x, -1);
     } else if (type == 2) {
-      int res = bit.walk2(x);
+      int res = bit.walk(x);
       if (res == -1 || res == sz(compress))
         cout << -1 << '\n';
       else cout << compress[res] << '\n';
@@ -49,12 +49,12 @@ int main() {
       cout << bit.query(x) << '\n';
     } else if (type == 4) {
       x = get_compressed_idx(x);
-      int res = bit.walk2(bit.query(x));
+      int res = bit.walk(bit.query(x));
       if (res == -1) cout << -1 << '\n';
       else cout << compress[res] << '\n';
     } else {
       x = get_compressed_idx(x);
-      int res = bit.walk2(bit.query(x - 1) + 1);
+      int res = bit.walk(bit.query(x - 1) + 1);
       if (res == sz(bit.s)) cout << -1 << '\n';
       else cout << compress[res] << '\n';
     }
diff --git a/tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp b/tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp
index 9ea8ac99..dec7c764 100644
--- a/tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp
+++ b/tests/library_checker_aizu_tests/data_structures/bit_walk.test.cpp
@@ -46,22 +46,13 @@ int main() {
         }
         return 1;
       };
-      int res = bit.walk2(order + 1);
+      int res = bit.walk(order + 1);
       assert(res == st.find_first(0, n, f));
       assert(res == st.find_first(k, n,
                       [&](ll x, int, int) -> bool {
                         return x > 0;
                       }));
       if (res == n) res = -1;
-      int res_lambda = -1;
-      bit.walk([&](int r, ll sum) {
-        if (sum > order) {
-          res_lambda = r - 1;
-          return 0;
-        }
-        return 1;
-      });
-      assert(res == res_lambda);
       cout << res << '\n';
     } else {
       if (bit.query(k, k + 1) == 1) {
@@ -78,24 +69,12 @@ int main() {
         }
         return 1;
       };
-      int res = bit.walk2(order);
+      int res = bit.walk(order);
       assert(max(res, 0) == st.find_first(0, n, f));
       assert(res == st.find_last(0, k + 1,
                       [&](ll x, int, int) -> bool {
                         return x > 0;
                       }));
-      int res_lambda = -1;
-      if (order) {
-        bit.walk([&](int r, ll sum) {
-          if (sum < order) {
-            res_lambda = r;
-            return 1;
-          }
-          res_lambda = r - 1;
-          return 0;
-        });
-      }
-      assert(res == res_lambda);
       cout << res << '\n';
     }
   }
diff --git a/tests/library_checker_aizu_tests/handmade_tests/seg_tree_find.test.cpp b/tests/library_checker_aizu_tests/handmade_tests/seg_tree_find.test.cpp
index b60ad939..67eec1ce 100644
--- a/tests/library_checker_aizu_tests/handmade_tests/seg_tree_find.test.cpp
+++ b/tests/library_checker_aizu_tests/handmade_tests/seg_tree_find.test.cpp
@@ -37,7 +37,7 @@ int main() {
       rngs.push_back({tl, tr, 1});
       return 1;
     };
-    int pos = min(bit.walk2(bit.query(l) + sum), r);
+    int pos = min(bit.walk(bit.query(l) + sum), r);
     reset();
     assert(pos == seg.find_first(l, r, f));
     assert(!empty(rngs));