Construct Binary Search Tree from Preorder Traversal LeetCode solution in Java

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class Solution {
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  public TreeNode bstFromPreorder(int[] preorder) {
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    return bst(preorder, 0, preorder.length - 1);
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  }
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  public TreeNode bst(int[] preorder, int start, int end) {
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    if (start > end) return null;
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    TreeNode root = new TreeNode(preorder[start]);
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    int breakPoint = start + 1;
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    while (breakPoint <= end && preorder[breakPoint] < preorder[start]) {
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      breakPoint++;
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    }
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    root.left = bst(preorder, start + 1, breakPoint - 1);
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    root.right = bst(preorder, breakPoint, end);
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    return root;
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  }
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}