House Robber II LeetCode solution in Java

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class Solution {
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  public int rob(int[] nums) {
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    if (nums.length == 1) {
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      return nums[0];
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    }
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    int[] t = new int[nums.length];
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    for (int i = 0; i < t.length; i++) {
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      t[i] = -1;
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    }
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    int[] k = new int[nums.length];
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    for (int i = 0; i < k.length; i++) {
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      k[i] = -1;
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    }
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    return Math.max(helper(nums, 0, 0, t), helper(nums, 1, 1, k));
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  }
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  static int helper(int[] nums, int i, int start, int[] t) {
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    if (start == 0 && i == nums.length - 2) {
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      return nums[i];
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    }
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    if (start == 1 && i == nums.length - 1) {
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      return nums[i];
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    }
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    if (start == 0 && i >= nums.length - 1) {
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      return 0;
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    }
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    if (start == 1 && i >= nums.length) {
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      return 0;
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    }
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    if (t[i] != -1) {
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      return t[i];
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    }
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    int pick = nums[i] + helper(nums, i + 2, start, t);
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    int notpick = helper(nums, i + 1, start, t);
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    t[i] = Math.max(pick, notpick);
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    return t[i];
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  }
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}