added double jump and sitting state

term1/seminar04_templates/01_sum_even/main.cpp

@@ -0,0 +1,18 @@
+#include <iostream>
+#include <vector>
+
+using std::cout, std::endl;
+
+int sumEven(const std::vector<int>& v) {
+    int sum = 0;
+    size_t s = v.size();
+    for (int i = 0; i < s; ++i)
+            if (v[i] % 2 == 0)
+                    sum += v[i];
+    return sum;
+}
+
+int main() {
+    std::vector<int> v {4, 8, 15, 16, 23, 42};
+    cout << sumEven(v) << endl;
+}