Added House Robber II.java

varunu28 · varunu28 · commit acd83cb1e33e · 2020-10-14T06:02:27.000-07:00
diff --git a/Medium/House Robber II.java b/Medium/House Robber II.java
@@ -0,0 +1,20 @@
+class Solution {
+  public int rob(int[] nums) {
+    if (nums.length == 1) {
+      return nums[0];
+    }
+    return Math.max(robHelper(nums, 0, nums.length - 2), robHelper(nums, 1, nums.length - 1));
+  }
+  
+  private int robHelper(int[] nums, int lower, int higher) {
+    int include = 0;
+    int exclude = 0;
+    for (int j = lower; j <= higher; j++) {
+      int includeIdx = include;
+      int excludeIdx = exclude;
+      include = excludeIdx + nums[j];
+      exclude = Math.max(excludeIdx, includeIdx);
+    }
+    return Math.max(include, exclude);
+  }
+}
