Merge pull request #11 from BodomMoon/leetcode198

Update house-robber.cpp

Author: kamyu104

C++/house-robber.cpp

@@ -0,0 +1,15 @@
+// Time:  O(n)
+// Space: O(1)
+
+class Solution {
+public:
+    int rob(vector<int>& nums) {
+        int last = 0, result = 0;
+        for (const auto& i : nums) {
+            auto tmp = result;
+            result = max(last + i, result);
+            last = tmp;
+        }
+        return result;
+    }
+};