solve house robber 2

Author: sora0319

house-robber-ii/sora0319.java

@@ -0,0 +1,21 @@
+class Solution {
+    public int rob(int[] nums) {
+        if (nums.length == 1) return nums[0];
+
+        return Math.max(dp(nums, 0, nums.length - 1),
+                        dp(nums, 1, nums.length));
+    }
+
+    private int dp(int[] nums, int start, int end) {
+        int back = 0;
+        int curr = 0;
+
+        for (int i = start; i < end; i++) {
+            int temp = curr;
+            curr = Math.max(back + nums[i], curr);
+            back = temp;
+        }
+
+        return curr;
+    }
+}