Added tasks 257-290.

Author: javadev

README.md

@@ -62,6 +62,7 @@
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 | 0240 |[Search a 2D Matrix II](src/main/kotlin/g0201_0300/s0240_search_a_2d_matrix_ii)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer | 460 | 66.08
+| 0275 |[H-Index II](src/main/kotlin/g0201_0300/s0275_h_index_ii)| Medium | Array, Binary_Search | 398 | 81.82
 
 #### Day 9
 
@@ -195,6 +196,7 @@
 
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+| 0264 |[Ugly Number II](src/main/kotlin/g0201_0300/s0264_ugly_number_ii)| Medium | Hash_Table, Dynamic_Programming, Math, Heap_Priority_Queue | 182 | 95.45
 | 0096 |[Unique Binary Search Trees](src/main/kotlin/g0001_0100/s0096_unique_binary_search_trees)| Medium | Top_100_Liked_Questions, Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree | 147 | 88.52
 
 #### Day 12
@@ -258,6 +260,7 @@
 
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+| 0279 |[Perfect Squares](src/main/kotlin/g0201_0300/s0279_perfect_squares)| Medium | Top_Interview_Questions, Dynamic_Programming, Math, Breadth_First_Search | 176 | 98.80
 
 ### Programming Skills I
 
@@ -622,6 +625,7 @@
 
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+| 0278 |[First Bad Version](src/main/kotlin/g0201_0300/s0278_first_bad_version)| Easy | Binary_Search, Interactive | 349 | 76.86
 
 #### Day 8 Binary Search Tree
 
@@ -834,6 +838,7 @@
 | 0242 |[Valid Anagram](src/main/kotlin/g0201_0300/s0242_valid_anagram)| Easy | Top_Interview_Questions, String, Hash_Table, Sorting | 251 | 87.65
 | 0049 |[Group Anagrams](src/main/kotlin/g0001_0100/s0049_group_anagrams)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting | 506 | 86.55
 | 0151 |[Reverse Words in a String](src/main/kotlin/g0101_0200/s0151_reverse_words_in_a_string)| Medium | String, Two_Pointers | 206 | 98.90
+| 0273 |[Integer to English Words](src/main/kotlin/g0201_0300/s0273_integer_to_english_words)| Hard | String, Math, Recursion | 273 | 82.93
 
 #### Udemy Binary Search
 
@@ -1132,6 +1137,7 @@
 
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+| 0290 |[Word Pattern](src/main/kotlin/g0201_0300/s0290_word_pattern)| Easy | String, Hash_Table | 177 | 89.55
 | 0763 |[Partition Labels](src/main/kotlin/g0701_0800/s0763_partition_labels)| Medium | Top_100_Liked_Questions, String, Hash_Table, Greedy, Two_Pointers | 235 | 84.75
 
 #### Day 8 String
@@ -1232,6 +1238,7 @@
 
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+| 0278 |[First Bad Version](src/main/kotlin/g0201_0300/s0278_first_bad_version)| Easy | Binary_Search, Interactive | 349 | 76.86
 | 0035 |[Search Insert Position](src/main/kotlin/g0001_0100/s0035_search_insert_position)| Easy | Top_100_Liked_Questions, Array, Binary_Search | 267 | 50.32
 
 #### Day 2 Two Pointers
@@ -1487,6 +1494,7 @@
 
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+| 0278 |[First Bad Version](src/main/kotlin/g0201_0300/s0278_first_bad_version)| Easy | Binary_Search, Interactive | 349 | 76.86
 | 0034 |[Find First and Last Position of Element in Sorted Array](src/main/kotlin/g0001_0100/s0034_find_first_and_last_position_of_element_in_sorted_array)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search | 228 | 83.38
 
 #### Day 6
@@ -1551,8 +1559,24 @@
 | 0322 |[Coin Change](src/main/kotlin/g0301_0400/s0322_coin_change)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_20, Level_2_Day_12_Dynamic_Programming | 332 | 50.68
 | 0300 |[Longest Increasing Subsequence](src/main/kotlin/g0201_0300/s0300_longest_increasing_subsequence)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Algorithm_II_Day_16_Dynamic_Programming, Binary_Search_II_Day_3, Dynamic_Programming_I_Day_18, Udemy_Dynamic_Programming | 318 | 82.28
 | 0295 |[Find Median from Data Stream](src/main/kotlin/g0201_0300/s0295_find_median_from_data_stream)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Design, Heap_Priority_Queue, Data_Stream | 2289 | 33.60
+| 0290 |[Word Pattern](src/main/kotlin/g0201_0300/s0290_word_pattern)| Easy | String, Hash_Table, Data_Structure_II_Day_7_String | 177 | 89.55
+| 0289 |[Game of Life](src/main/kotlin/g0201_0300/s0289_game_of_life)| Medium | Top_Interview_Questions, Array, Matrix, Simulation | 174 | 96.97
 | 0287 |[Find the Duplicate Number](src/main/kotlin/g0201_0300/s0287_find_the_duplicate_number)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Binary_Search_II_Day_5 | 656 | 66.21
+| 0284 |[Peeking Iterator](src/main/kotlin/g0201_0300/s0284_peeking_iterator)| Medium | Array, Design, Iterator | 286 | 62.50
 | 0283 |[Move Zeroes](src/main/kotlin/g0201_0300/s0283_move_zeroes)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Algorithm_I_Day_3_Two_Pointers, Programming_Skills_I_Day_6_Array, Udemy_Arrays | 516 | 79.07
+| 0282 |[Expression Add Operators](src/main/kotlin/g0201_0300/s0282_expression_add_operators)| Hard | String, Math, Backtracking | 367 | 85.71
+| 0279 |[Perfect Squares](src/main/kotlin/g0201_0300/s0279_perfect_squares)| Medium | Top_Interview_Questions, Dynamic_Programming, Math, Breadth_First_Search, Dynamic_Programming_I_Day_21 | 176 | 98.80
+| 0278 |[First Bad Version](src/main/kotlin/g0201_0300/s0278_first_bad_version)| Easy | Binary_Search, Interactive, Algorithm_I_Day_1_Binary_Search, Binary_Search_I_Day_5, Level_1_Day_7_Binary_Search | 349 | 76.86
+| 0275 |[H-Index II](src/main/kotlin/g0201_0300/s0275_h_index_ii)| Medium | Array, Binary_Search, Binary_Search_II_Day_8 | 398 | 81.82
+| 0274 |[H-Index](src/main/kotlin/g0201_0300/s0274_h_index)| Medium | Array, Sorting, Counting_Sort | 291 | 45.45
+| 0273 |[Integer to English Words](src/main/kotlin/g0201_0300/s0273_integer_to_english_words)| Hard | String, Math, Recursion, Udemy_Strings | 273 | 82.93
+| 0268 |[Missing Number](src/main/kotlin/g0201_0300/s0268_missing_number)| Easy | Top_Interview_Questions, Array, Hash_Table, Math, Sorting, Binary_Search, Bit_Manipulation | 380 | 83.49
+| 0264 |[Ugly Number II](src/main/kotlin/g0201_0300/s0264_ugly_number_ii)| Medium | Hash_Table, Dynamic_Programming, Math, Heap_Priority_Queue, Dynamic_Programming_I_Day_11 | 182 | 95.45
+| 0263 |[Ugly Number](src/main/kotlin/g0201_0300/s0263_ugly_number)| Easy | Math | 243 | 64.10
+| 0262 |[Trips and Users](src/main/kotlin/g0201_0300/s0262_trips_and_users)| Hard | Database | 577 | 63.97
+| 0260 |[Single Number III](src/main/kotlin/g0201_0300/s0260_single_number_iii)| Medium | Array, Bit_Manipulation | 222 | 100.00
+| 0258 |[Add Digits](src/main/kotlin/g0201_0300/s0258_add_digits)| Easy | Math, Simulation, Number_Theory | 234 | 71.64
+| 0257 |[Binary Tree Paths](src/main/kotlin/g0201_0300/s0257_binary_tree_paths)| Easy | String, Depth_First_Search, Tree, Binary_Tree, Backtracking | 320 | 72.84
 | 0242 |[Valid Anagram](src/main/kotlin/g0201_0300/s0242_valid_anagram)| Easy | Top_Interview_Questions, String, Hash_Table, Sorting, Data_Structure_I_Day_6_String, Programming_Skills_I_Day_11_Containers_and_Libraries, Udemy_Strings | 251 | 87.65
 | 0241 |[Different Ways to Add Parentheses](src/main/kotlin/g0201_0300/s0241_different_ways_to_add_parentheses)| Medium | String, Dynamic_Programming, Math, Recursion, Memoization | 294 | 73.47
 | 0240 |[Search a 2D Matrix II](src/main/kotlin/g0201_0300/s0240_search_a_2d_matrix_ii)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Data_Structure_II_Day_4_Array, Binary_Search_II_Day_8 | 460 | 66.08

src/main/kotlin/g0101_0200/s0177_nth_highest_salary/readme.md

@@ -72,6 +72,7 @@ DECLARE M INT;
 SET M=N-1;
   RETURN (
       # Write your MySQL query statement below.
+      # #Medium #Database #2022_10_18_Time_338_ms_(86.68%)_Space_0B_(100.00%)
       SELECT DISTINCT Salary FROM Employee ORDER BY Salary DESC LIMIT M, 1
   );
 END

src/main/kotlin/g0201_0300/s0257_binary_tree_paths/readme.md

@@ -0,0 +1,81 @@
+[![](https://img.shields.io/github/stars/javadev/LeetCode-in-Kotlin?label=Stars&style=flat-square)](https://github.com/javadev/LeetCode-in-Kotlin)
+[![](https://img.shields.io/github/forks/javadev/LeetCode-in-Kotlin?label=Fork%20me%20on%20GitHub%20&style=flat-square)](https://github.com/javadev/LeetCode-in-Kotlin/fork)
+
+## 257\. Binary Tree Paths
+
+Easy
+
+Given the `root` of a binary tree, return _all root-to-leaf paths in **any order**_.
+
+A **leaf** is a node with no children.
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2021/03/12/paths-tree.jpg)
+
+**Input:** root = [1,2,3,null,5]
+
+**Output:** ["1->2->5","1->3"]
+
+**Example 2:**
+
+**Input:** root = [1]
+
+**Output:** ["1"]
+
+**Constraints:**
+
+*   The number of nodes in the tree is in the range `[1, 100]`.
+*   `-100 <= Node.val <= 100`
+
+## Solution
+
+```kotlin
+import com_github_leetcode.TreeNode
+
+/*
+ * Example:
+ * var ti = TreeNode(5)
+ * var v = ti.`val`
+ * Definition for a binary tree node.
+ * class TreeNode(var `val`: Int) {
+ *     var left: TreeNode? = null
+ *     var right: TreeNode? = null
+ * }
+ */
+class Solution {
+    private var result: MutableList<String>? = null
+    private var sb: StringBuilder? = null
+    fun binaryTreePaths(root: TreeNode?): List<String> {
+        result = ArrayList()
+        if (root == null) {
+            return result as ArrayList<String>
+        }
+        sb = StringBuilder()
+        walkThrough(root)
+        return result as ArrayList<String>
+    }
+
+    private fun walkThrough(root: TreeNode?) {
+        assert(root != null)
+        var length = sb!!.length
+        sb!!.append(root!!.`val`)
+        length = sb!!.length - length
+        if (root.left == null && root.right == null) {
+            // leaf node.
+            result!!.add(sb.toString())
+            sb!!.delete(sb!!.length - length, sb!!.length)
+            return
+        }
+        sb!!.append("->")
+        length += 2
+        if (root.left != null) {
+            walkThrough(root.left)
+        }
+        if (root.right != null) {
+            walkThrough(root.right)
+        }
+        sb!!.delete(sb!!.length - length, sb!!.length)
+    }
+}
+```

src/main/kotlin/g0201_0300/s0258_add_digits/readme.md

@@ -0,0 +1,43 @@
+[![](https://img.shields.io/github/stars/javadev/LeetCode-in-Kotlin?label=Stars&style=flat-square)](https://github.com/javadev/LeetCode-in-Kotlin)
+[![](https://img.shields.io/github/forks/javadev/LeetCode-in-Kotlin?label=Fork%20me%20on%20GitHub%20&style=flat-square)](https://github.com/javadev/LeetCode-in-Kotlin/fork)
+
+## 258\. Add Digits
+
+Easy
+
+Given an integer `num`, repeatedly add all its digits until the result has only one digit, and return it.
+
+**Example 1:**
+
+**Input:** num = 38
+
+**Output:** 2
+
+**Explanation:** The process is 38 --> 3 + 8 --> 11 11 --> 1 + 1 --> 2 Since 2 has only one digit, return it.
+
+**Example 2:**
+
+**Input:** num = 0
+
+**Output:** 0
+
+**Constraints:**
+
+*   <code>0 <= num <= 2<sup>31</sup> - 1</code>
+
+**Follow up:** Could you do it without any loop/recursion in `O(1)` runtime?
+
+## Solution
+
+```kotlin
+class Solution {
+    fun addDigits(num: Int): Int {
+        if (num == 0) {
+            return 0
+        }
+        return if (num % 9 == 0) {
+            9
+        } else num % 9
+    }
+}
+```

src/main/kotlin/g0201_0300/s0260_single_number_iii/readme.md

@@ -0,0 +1,58 @@
+[![](https://img.shields.io/github/stars/javadev/LeetCode-in-Kotlin?label=Stars&style=flat-square)](https://github.com/javadev/LeetCode-in-Kotlin)
+[![](https://img.shields.io/github/forks/javadev/LeetCode-in-Kotlin?label=Fork%20me%20on%20GitHub%20&style=flat-square)](https://github.com/javadev/LeetCode-in-Kotlin/fork)
+
+## 260\. Single Number III
+
+Medium
+
+Given an integer array `nums`, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the two elements that appear only once. You can return the answer in **any order**.
+
+You must write an algorithm that runs in linear runtime complexity and uses only constant extra space.
+
+**Example 1:**
+
+**Input:** nums = [1,2,1,3,2,5]
+
+**Output:** [3,5] **Explanation: ** [5, 3] is also a valid answer.
+
+**Example 2:**
+
+**Input:** nums = [-1,0]
+
+**Output:** [-1,0]
+
+**Example 3:**
+
+**Input:** nums = [0,1]
+
+**Output:** [1,0]
+
+**Constraints:**
+
+*   <code>2 <= nums.length <= 3 * 10<sup>4</sup></code>
+*   <code>-2<sup>31</sup> <= nums[i] <= 2<sup>31</sup> - 1</code>
+*   Each integer in `nums` will appear twice, only two integers will appear once.
+
+## Solution
+
+```kotlin
+class Solution {
+    fun singleNumber(nums: IntArray): IntArray {
+        var xorSum = 0
+        for (num in nums) {
+            // will give xor of required nos
+            xorSum = xorSum xor num
+        }
+        // find rightmost bit which is set
+        val rightBit = xorSum and -xorSum
+        var a = 0
+        for (num in nums) {
+            // xor only those number whose rightmost bit is set
+            if (num and rightBit != 0) {
+                a = a xor num
+            }
+        }
+        return intArrayOf(a, a xor xorSum)
+    }
+}
+```