add: house-robber

Author: maxyzli

README.md

@@ -1,6 +1,6 @@
 # LeetCode
 
-![](https://img.shields.io/badge/solved-226-337ab7?style=for-the-badge&logo=appveyor.svg) 
+![](https://img.shields.io/badge/solved-227-337ab7?style=for-the-badge&logo=appveyor.svg) 
 ![](https://img.shields.io/badge/language-Java-yellow?style=for-the-badge&logo=appveyor.svg)
 
 LeetCode Solution in Java
@@ -373,6 +373,7 @@ LeetCode Solution in Java
 |96|[Unique Binary Search Trees (Classic)](https://leetcode.com/problems/unique-binary-search-trees/)|[Java](tree/unique-binary-search-trees/README.md)|Medium|
 |115|[Distinct Subsequences](https://leetcode.com/problems/distinct-subsequences/)|[Java](array-string/distinct-subsequences/README.md)|Hard|
 |131|[Palindrome Partitioning](https://leetcode.com/problems/palindrome-partitioning/)|[Java](dynamic-programming/palindrome-partitioning/README.md)|Medium|
+|198|[House Robber](https://leetcode.com/problems/house-robber/)|[Java](dynamic-programming/house-robber/README.md)|Medium|
 |221|[Maximal Square (Classic)](https://leetcode.com/problems/maximal-square/submissions/)|[Java](dynamic-programming/submissions/README.md)|Medium|
 |300|[Longest Increasing Subsequence (Classic)](https://leetcode.com/problems/longest-increasing-subsequence/)|[Java](dynamic-programming/longest-increasing-subsequence/README.md)|Medium|
 |313|[Super Ugly Number (Classic)](https://leetcode.com/problems/super-ugly-number/)|[Java](dynamic-programming/super-ugly-number/README.md)|Medium|

dynamic-programming/house-robber/README.md

@@ -0,0 +1,59 @@
+# House Robber
+
+## Solution 1
+
+DFS
+
+```java
+/**
+ * Question   : 198. House Robber
+ * Complexity : Time: O(2^n) ; Space: O(n)
+ * Topics     : DP
+ */
+class Solution {
+    public int rob(int[] nums) {
+        if (nums == null || nums.length == 0) {
+            return 0;
+        }
+        return robUtil(nums, nums.length);
+    }
+
+    private int robUtil(int[] nums, int n) {
+        if (n <= 0) {
+            return 0;
+        }
+        return Math.max(nums[n - 1] + robUtil(nums, n - 2), robUtil(nums, n - 1));
+    }
+}
+```
+
+## Solution 2
+
+DP
+
+```java
+/**
+ * Question   : 198. House Robber
+ * Complexity : Time: O(n) ; Space: O(n)
+ * Topics     : DP
+ */
+class Solution {
+    public int rob(int[] nums) {
+        if (nums == null || nums.length == 0) {
+            return 0;
+        }
+        
+        int n = nums.length;
+        
+        int[] dp = new int[n + 1];
+        dp[0] = 0;
+        dp[1] = nums[0];
+        
+        for (int i = 2; i <= n; i++) {
+            dp[i] = Math.max(dp[i - 1], nums[i - 1] + dp[i - 2]);
+        }
+        
+        return dp[n];
+    }
+}
+```