Add 198_House_Robber.java

Author: Sean Prashad

Dynamic Programming/198_House_Robber.java

@@ -0,0 +1,25 @@
+class Solution {
+    public int rob(int[] nums) {
+        if (nums == null || nums.length == 0) {
+            return 0;
+        }
+
+        int[] memo = new int[nums.length + 1];
+        Arrays.fill(memo, -1);
+        return robHouses(nums, nums.length - 1, memo);
+    }
+
+    private int robHouses(int[] houses, int houseNo, int[] memo) {
+        if (houseNo < 0) {
+            return 0;
+        }
+        if (memo[houseNo] >= 0) {
+            return memo[houseNo];
+        }
+
+        int result = Math.max(robHouses(houses, houseNo - 2, memo) + houses[houseNo],
+                robHouses(houses, houseNo - 1, memo));
+        memo[houseNo] = result;
+        return result;
+    }
+}