Create maximum-sum-with-exactly-k-elements.cpp

Author: kamyu104

C++/maximum-sum-with-exactly-k-elements.cpp

@@ -0,0 +1,10 @@
+// Time:  O(n)
+// Space: O(1)
+
+// math
+class Solution {
+public:
+    int maximizeSum(vector<int>& nums, int k) {
+        return *max_element(cbegin(nums), cend(nums)) * k + k * (k - 1) / 2;
+    }
+};