adding works

homework/add-even/addEven.hpp

@@ -1,8 +1,14 @@
 #pragma once
+#include <algorithm>
 #include <vector>
 
 int addEven(const std::vector<int>& numbers) {
-    // TODO: Your implementation goes here
-    // Below return is only to make this function compile now
-    return -1;
+    int result = 0;
+    std::for_each(numbers.begin(), numbers.end(), [&result](int el) {
+        if (el % 2 == 0) {
+            result += el;
+        }
+    });
+
+    return result;
 }