diff --git a/clojure/412.clj b/clojure/412.clj
deleted file mode 100644
index 4698221..0000000
--- a/clojure/412.clj
+++ /dev/null
@@ -1,31 +0,0 @@
-(ns clojure.412
-  "Leetcode: 412
-   Name: Fizz Buzz" 
-  (:require [clojure.test :refer [deftest is run-tests]]))
-
-(defn fizz-buzz [n]
-  {:pre [(and (integer? n) (<= 1 n (Math/pow 10 4)))]}
-  (loop [vector-n (range 1 (inc n))
-         result []]
-    (if (empty? vector-n)
-      result
-      (let [current-num (first vector-n)
-            next-vector (rest vector-n)
-            fizz-buzz-result (cond
-                               (and (zero? (mod current-num 3))
-                                    (zero? (mod current-num 5))) "FizzBuzz"
-                               (zero? (mod current-num 3)) "Fizz"
-                               (zero? (mod current-num 5)) "Buzz"
-                               :else (str current-num))]
-        (recur next-vector (conj result fizz-buzz-result))))))
-
-(deftest test-fizz-buzz
-  (is (= (fizz-buzz 1) ["1"]))
-  (is (= (fizz-buzz 3) ["1" "2" "Fizz"]))
-  (is (= (fizz-buzz 5) ["1" "2" "Fizz" "4" "Buzz"]))
-  (is (= (fizz-buzz 15) ["1" "2" "Fizz" "4" "Buzz" "Fizz" "7" "8" "Fizz" "Buzz" "11" "Fizz" "13" "14" "FizzBuzz"]))
-  (is (thrown? AssertionError (fizz-buzz 10001)))
-  (is (thrown? AssertionError (fizz-buzz 0)))
-  (is (thrown? AssertionError (fizz-buzz -1))))
-
-(run-tests)
\ No newline at end of file
diff --git a/ruby/412.rb b/ruby/412.rb
deleted file mode 100644
index 537202d..0000000
--- a/ruby/412.rb
+++ /dev/null
@@ -1,38 +0,0 @@
-require 'minitest/autorun'
-
-def fizz_buzz(n)
-  pre_condition(n)
-  result = []
-
-  (1..n).each do |i|
-    if i % 3 == 0 && i % 5 == 0
-      result << "FizzBuzz"
-    elsif i % 3 == 0
-      result << "Fizz"
-    elsif i % 5 == 0
-      result << "Buzz"
-    else
-      result << i.to_s
-    end
-  end
-
-  result
-end
-
-def pre_condition(value)
-  raise ArgumentError, "Argument must be an integer" unless value.is_a? Integer
-end
-
-class TestFizzBuzz < Minitest::Test
-  def test_fizz_buzz
-    assert_equal ["1", "2", "Fizz"], fizz_buzz(3)
-    assert_equal ["1", "2", "Fizz", "4", "Buzz"], fizz_buzz(5)
-    assert_equal ["1", "2", "Fizz", "4", "Buzz", "Fizz", "7", "8", "Fizz", "Buzz", "11", "Fizz", "13", "14", "FizzBuzz"], fizz_buzz(15)
-  end
-
-  def test_pre_condition
-    assert_raises ArgumentError do
-      fizz_buzz("a")
-    end
-  end
-end
diff --git a/solutions/0401-0500/0412-fizz-buzz/README.md b/solutions/0401-0500/0412-fizz-buzz/README.md
new file mode 100644
index 0000000..0d3f421
--- /dev/null
+++ b/solutions/0401-0500/0412-fizz-buzz/README.md
@@ -0,0 +1,15 @@
+# 412. Fizz Buzz
+
+[LeetCode problem 412](https://leetcode.com/problems/fizz-buzz/)
+
+- **Difficulty**: Easy
+- **Tags**: math, string, simulation
+
+## Description
+
+Given an integer `n`, return a string array `answer` (1-indexed) where:
+
+- `answer[i] == "FizzBuzz"` if `i` is divisible by 3 and 5.
+- `answer[i] == "Fizz"` if `i` is divisible by 3.
+- `answer[i] == "Buzz"` if `i` is divisible by 5.
+- `answer[i] == i` (as a string) otherwise.
diff --git a/solutions/0401-0500/0412-fizz-buzz/solution.cpp b/solutions/0401-0500/0412-fizz-buzz/solution.cpp
new file mode 100644
index 0000000..a4a7981
--- /dev/null
+++ b/solutions/0401-0500/0412-fizz-buzz/solution.cpp
@@ -0,0 +1,24 @@
+#include "solution.hpp"
+
+namespace leetcode::p0412 {
+
+std::vector<std::string> solve(int n) {
+    std::vector<std::string> result;
+    result.reserve(static_cast<std::size_t>(n));
+
+    for (int i = 1; i <= n; ++i) {
+        if (i % 15 == 0) {
+            result.emplace_back("FizzBuzz");
+        } else if (i % 3 == 0) {
+            result.emplace_back("Fizz");
+        } else if (i % 5 == 0) {
+            result.emplace_back("Buzz");
+        } else {
+            result.push_back(std::to_string(i));
+        }
+    }
+
+    return result;
+}
+
+} // namespace leetcode::p0412
diff --git a/solutions/0401-0500/0412-fizz-buzz/solution.hpp b/solutions/0401-0500/0412-fizz-buzz/solution.hpp
new file mode 100644
index 0000000..2f18156
--- /dev/null
+++ b/solutions/0401-0500/0412-fizz-buzz/solution.hpp
@@ -0,0 +1,11 @@
+#pragma once
+
+#include <string>
+#include <vector>
+
+namespace leetcode::p0412 {
+
+// optimized: O(n) time, O(n) space (excluding the output) — one pass.
+std::vector<std::string> solve(int n);
+
+} // namespace leetcode::p0412
diff --git a/solutions/0401-0500/0412-fizz-buzz/test.cpp b/solutions/0401-0500/0412-fizz-buzz/test.cpp
new file mode 100644
index 0000000..5d29b5a
--- /dev/null
+++ b/solutions/0401-0500/0412-fizz-buzz/test.cpp
@@ -0,0 +1,26 @@
+#include <catch2/catch_test_macros.hpp>
+
+#include "solution.hpp"
+
+TEST_CASE("Problem 412", "[p0412]") {
+    CHECK(leetcode::p0412::solve(1) == std::vector<std::string>{"1"});
+    CHECK(leetcode::p0412::solve(3) == std::vector<std::string>{"1", "2", "Fizz"});
+    CHECK(leetcode::p0412::solve(5) == std::vector<std::string>{"1", "2", "Fizz", "4", "Buzz"});
+    CHECK(leetcode::p0412::solve(15) == std::vector<std::string>{
+                                            "1",
+                                            "2",
+                                            "Fizz",
+                                            "4",
+                                            "Buzz",
+                                            "Fizz",
+                                            "7",
+                                            "8",
+                                            "Fizz",
+                                            "Buzz",
+                                            "11",
+                                            "Fizz",
+                                            "13",
+                                            "14",
+                                            "FizzBuzz",
+                                        });
+}