feat: add generic find_max_min implementation with tests

arrays/find_max_min.cpp

@@ -0,0 +1,84 @@
+/**
+ * @file
+ * @brief Program to find maximum and minimum element in an array
+ *
+ * @details
+ * This program demonstrates how to find the maximum and minimum values
+ * in an array of elements. It is implemented as a template function so
+ * it works with any comparable data type.
+ *
+ * The algorithm simply iterates through the array once, updating the
+ * maximum and minimum values as needed. This results in \f$O(n)\f$ time
+ * complexity and \f$O(1)\f$ space complexity.
+ */
+
+#include <cassert>   /// for assert
+#include <iostream>  /// for std::cout, std::endl
+#include <vector>    /// for std::vector
+#include <utility>   /// for std::pair
+
+/**
+ * @namespace arrays
+ * @brief Array-based algorithms
+ */
+namespace arrays {
+/**
+ * @namespace find_max_min
+ * @brief Functions for finding maximum and minimum values
+ */
+namespace find_max_min {
+/**
+ * @brief Find maximum and minimum in an array
+ * @tparam T data type of elements (must support comparisons)
+ * @param arr input array
+ * @return std::pair<T, T> containing {max, min}
+ */
+template <typename T>
+std::pair<T, T> findMaxMin(const std::vector<T>& arr) {
+    assert(!arr.empty());  // array must not be empty
+    T maxVal = arr[0];
+    T minVal = arr[0];
+    for (size_t i = 1; i < arr.size(); i++) {
+        if (arr[i] > maxVal) {
+            maxVal = arr[i];
+        }
+        if (arr[i] < minVal) {
+            minVal = arr[i];
+        }
+    }
+    return {maxVal, minVal};
+}
+}  // namespace find_max_min
+}  // namespace arrays
+
+/**
+ * @brief Self-test implementation
+ */
+static void test() {
+    using arrays::find_max_min::findMaxMin;
+
+    std::vector<int> vec1 = {3, 1, 7, -5, 9};
+    auto result1 = findMaxMin(vec1);
+    assert(result1.first == 9 && result1.second == -5);
+
+    std::vector<float> vec2 = {1.5, 2.5, 0.5};
+    auto result2 = findMaxMin(vec2);
+    assert(result2.first == 2.5f && result2.second == 0.5f);
+
+    std::vector<char> vec3 = {'a', 'z', 'm'};
+    auto result3 = findMaxMin(vec3);
+    assert(result3.first == 'z' && result3.second == 'a');
+
+    std::vector<int> vec4 = {42};
+    auto result4 = findMaxMin(vec4);
+    assert(result4.first == 42 && result4.second == 42);
+}
+
+/**
+ * @brief Main function
+ */
+int main() {
+    test();
+    std::cout << "All tests passed!\n";
+    return 0;
+}