cpp: add “198. House Robber”

Signed-off-by: Matej Focko <me@mfocko.xyz>

cpp/house-robber.cpp

@@ -0,0 +1,22 @@
+class Solution {
+    static int get(const std::vector<int> &nums, int i) {
+        if (i < 0 || i >= static_cast<int>(nums.size())) {
+            return 0;
+        }
+
+        return nums[i];
+    }
+
+  public:
+    int rob(std::vector<int> nums) {
+        if (nums.size() == 0) {
+            return 0;
+        }
+
+        for (int i = 1; i < static_cast<int>(nums.size()); ++i) {
+            nums[i] = std::max(nums[i - 1], get(nums, i - 2) + nums[i]);
+        }
+
+        return nums.back();
+    }
+};