Create 213. House Robber II

Author: rajatag03

213. House Robber II

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+class Solution {
+    public int rob(int[] nums) {
+        if(nums.length==1) return nums[0];
+        if(nums.length==2) return Math.max(nums[0],nums[1]);
+        
+        //0th index - n-2 index
+        int x = helper(0,nums.length-1,nums);
+        //1st index - n-1 index
+        int y = helper(1,nums.length,nums);
+        
+        return Math.max(x,y);
+    }
+    
+    private int helper(int start,int end,int[] nums){
+        int[] dp = new int[end];
+        dp[start]=nums[start];
+        dp[start+1] = Math.max(nums[start],nums[start+1]);
+        for(int index=start+2;index<end;index++){
+            dp[index] = Math.max(dp[index-2]+nums[index],dp[index-1]);
+        }
+        return dp[dp.length-1];
+    }
+}