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2023-02-13 update: added "108. Convert Sorted Array to Binary Search Tree"
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‎README.md

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@@ -12,24 +12,25 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
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### Easy
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| Name | Link to LeetCode | Link to solution |
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|----------------------------------------|---------------------------------------------------------------------------------|------------------------------------------------------------|
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| 1. Two Sum | [Link](https://leetcode.com/problems/two-sum/) | [Link](./lib/easy/two_sum.dart) |
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| 9. Palindrome Number | [Link](https://leetcode.com/problems/palindrome-number/) | [Link](./lib/easy/palindrome_number.dart) |
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| 13. Roman to Integer | [Link](https://leetcode.com/problems/roman-to-integer/) | [Link](./lib/easy/roman_to_integer.dart) |
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| 14. Longest Common Prefix | [Link](https://leetcode.com/problems/longest-common-prefix/) | [Link](./lib/easy/longest_common_prefix.dart) |
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| 20. Valid Parentheses | [Link](https://leetcode.com/problems/valid-parentheses/) | [Link](./lib/easy/valid_parentheses.dart) |
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| 21. Merge Two Sorted Lists | [Link](https://leetcode.com/problems/merge-two-sorted-lists/) | [Link](./lib/easy/merge_two_sorted_lists.dart) |
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| 27. Remove Element | [Link](https://leetcode.com/problems/remove-element/) | [Link](./lib/easy/remove_element.dart) |
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| 35. Search Insert Position | [Link](https://leetcode.com/problems/search-insert-position/) | [Link](./lib/easy/search_insert_position.dart) |
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| 58. Length of Last Word | [Link](https://leetcode.com/problems/length-of-last-word/) | [Link](./lib/easy/length_of_last_word.dart) |
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| 66. Plus One | [Link](https://leetcode.com/problems/plus-one/) | [Link](./lib/easy/plus_one.dart) |
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| 67. Add Binary | [Link](https://leetcode.com/problems/add-binary/) | [Link](./lib/easy/add_binary.dart) |
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| 69. Sqrt(x) | [Link](https://leetcode.com/problems/sqrtx/) | [Link](./lib/easy/sqrt_x.dart) |
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| 70. Climbing Stairs | [Link](https://leetcode.com/problems/climbing-stairs/) | [Link](./lib/easy/climbing_stairs.dart) |
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| 83. Remove Duplicates from Sorted List | [Link](https://leetcode.com/problems/remove-duplicates-from-sorted-list/) | [Link](./lib/easy/remove_duplicates_from_sorted_list.dart) |
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| 88. Merge Sorted Array | [Link](https://leetcode.com/problems/merge-sorted-array/) | [Link](./lib/easy/merge_sorted_array.dart) |
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| 94. Binary Tree Inorder Traversal | [Link](https://leetcode.com/problems/binary-tree-inorder-traversal/) | [Link](./lib/easy/binary_tree_inorder_traversal.dart) |
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| 100. Same Tree | [Link](https://leetcode.com/problems/same-tree/) | [Link](./lib/easy/same_tree.dart) |
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| 101. Symmetric Tree | [Link](https://leetcode.com/problems/symmetric-tree/) | [Link](./lib/easy/symmetric_tree.dart) |
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| 104. Maximum Depth of Binary Tree | [Link](https://leetcode.com/problems/maximum-depth-of-binary-tree/description/) | [Link](./lib/easy/maximum_depth_of_binary_tree.dart) |
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| Name | Link to LeetCode | Link to solution |
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|-------------------------------------------------|-----------------------------------------------------------------------------------|--------------------------------------------------------------------|
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| 1. Two Sum | [Link](https://leetcode.com/problems/two-sum/) | [Link](./lib/easy/two_sum.dart) |
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| 9. Palindrome Number | [Link](https://leetcode.com/problems/palindrome-number/) | [Link](./lib/easy/palindrome_number.dart) |
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| 13. Roman to Integer | [Link](https://leetcode.com/problems/roman-to-integer/) | [Link](./lib/easy/roman_to_integer.dart) |
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| 14. Longest Common Prefix | [Link](https://leetcode.com/problems/longest-common-prefix/) | [Link](./lib/easy/longest_common_prefix.dart) |
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| 20. Valid Parentheses | [Link](https://leetcode.com/problems/valid-parentheses/) | [Link](./lib/easy/valid_parentheses.dart) |
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| 21. Merge Two Sorted Lists | [Link](https://leetcode.com/problems/merge-two-sorted-lists/) | [Link](./lib/easy/merge_two_sorted_lists.dart) |
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| 27. Remove Element | [Link](https://leetcode.com/problems/remove-element/) | [Link](./lib/easy/remove_element.dart) |
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| 35. Search Insert Position | [Link](https://leetcode.com/problems/search-insert-position/) | [Link](./lib/easy/search_insert_position.dart) |
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| 58. Length of Last Word | [Link](https://leetcode.com/problems/length-of-last-word/) | [Link](./lib/easy/length_of_last_word.dart) |
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| 66. Plus One | [Link](https://leetcode.com/problems/plus-one/) | [Link](./lib/easy/plus_one.dart) |
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| 67. Add Binary | [Link](https://leetcode.com/problems/add-binary/) | [Link](./lib/easy/add_binary.dart) |
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| 69. Sqrt(x) | [Link](https://leetcode.com/problems/sqrtx/) | [Link](./lib/easy/sqrt_x.dart) |
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| 70. Climbing Stairs | [Link](https://leetcode.com/problems/climbing-stairs/) | [Link](./lib/easy/climbing_stairs.dart) |
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| 83. Remove Duplicates from Sorted List | [Link](https://leetcode.com/problems/remove-duplicates-from-sorted-list/) | [Link](./lib/easy/remove_duplicates_from_sorted_list.dart) |
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| 88. Merge Sorted Array | [Link](https://leetcode.com/problems/merge-sorted-array/) | [Link](./lib/easy/merge_sorted_array.dart) |
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| 94. Binary Tree Inorder Traversal | [Link](https://leetcode.com/problems/binary-tree-inorder-traversal/) | [Link](./lib/easy/binary_tree_inorder_traversal.dart) |
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| 100. Same Tree | [Link](https://leetcode.com/problems/same-tree/) | [Link](./lib/easy/same_tree.dart) |
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| 101. Symmetric Tree | [Link](https://leetcode.com/problems/symmetric-tree/) | [Link](./lib/easy/symmetric_tree.dart) |
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| 104. Maximum Depth of Binary Tree | [Link](https://leetcode.com/problems/maximum-depth-of-binary-tree/description/) | [Link](./lib/easy/maximum_depth_of_binary_tree.dart) |
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| 108. Convert Sorted Array to Binary Search Tree | [Link](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/) | [Link](./lib/easy/convert_sorted_array_to_binary_search_tree.dart) |

‎lib/easy/convert_sorted_array_to_binary_search_tree.dart

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import '../common/tree_node.dart';
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// https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/
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class Solution {
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TreeNode? sortedArrayToBST(List<int> nums) {
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return _toBST(nums, 0, nums.length - 1);
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}
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TreeNode? _toBST(List<int> nums, int start, int end) {
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if (start > end) {
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return null;
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}
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var middle = (start + end) ~/ 2;
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var node = TreeNode(nums[middle]);
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node.left = _toBST(nums, start, middle - 1);
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node.right = _toBST(nums, middle + 1, end);
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return node;
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}
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}

‎test/common/binary_tree_helper.dart

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import 'package:leetcode_dart/common/tree_node.dart';
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class LinkedListHelper {
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LinkedListHelper._();
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class BinaryTreeHelper {
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BinaryTreeHelper._();
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static bool areEqual(TreeNode? f, TreeNode? s) {
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while (f != null && s != null) {

‎test/easy/convert_sorted_array_to_binary_search_tree_test.dart

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import 'package:leetcode_dart/common/tree_node.dart';
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import 'package:leetcode_dart/easy/convert_sorted_array_to_binary_search_tree.dart';
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import 'package:test/test.dart';
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import '../common/binary_tree_helper.dart';
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void main() {
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group(
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'Example tests',
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() {
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final csatbst = Solution();
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test(
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'[0, -10, 5, null, -3, null, 9]',
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() => expect(
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true,
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BinaryTreeHelper.areEqual(
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TreeNode(
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0,
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TreeNode(
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-10,
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null,
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TreeNode(-3),
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),
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TreeNode(
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5,
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null,
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TreeNode(9),
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),
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),
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csatbst.sortedArrayToBST(
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[-10, -3, 0, 5, 9],
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),
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),
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),
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);
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test(
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'3, null, 1',
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() => expect(
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true,
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BinaryTreeHelper.areEqual(
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TreeNode(
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3,
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null,
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TreeNode(1),
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),
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csatbst.sortedArrayToBST([3, 1]),
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),
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),
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);
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},
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);
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}

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