Added tasks 128-152

Author: javadev

README.md

@@ -137,6 +137,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0139 |[Word Break](src/main/scala/g0101_0200/s0139_word_break/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max\*N)_Space_O(M+N+max) | 482 | 66.67
 
 #### Day 16 Dynamic Programming
 
@@ -372,6 +373,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0152 |[Maximum Product Subarray](src/main/scala/g0101_0200/s0152_maximum_product_subarray/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 472 | 100.00
 
 #### Day 7
 
@@ -388,6 +390,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0139 |[Word Break](src/main/scala/g0101_0200/s0139_word_break/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max\*N)_Space_O(M+N+max) | 482 | 66.67
 | 0042 |[Trapping Rain Water](src/main/scala/g0001_0100/s0042_trapping_rain_water/Solution.scala)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1) | 521 | 87.88
 
 #### Day 10
@@ -591,6 +594,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0138 |[Copy List with Random Pointer](src/main/scala/g0101_0200/s0138_copy_list_with_random_pointer/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Big_O_Time_O(N)_Space_O(N) | 477 | 96.00
 
 #### Day 15
 
@@ -769,6 +773,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0142 |[Linked List Cycle II](src/main/scala/g0101_0200/s0142_linked_list_cycle_ii/Solution.scala)| Medium | Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) | 501 | 61.54
 
 #### Day 5 Greedy
 
@@ -853,6 +858,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0148 |[Sort List](src/main/scala/g0101_0200/s0148_sort_list/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(log(N))_Space_O(log(N)) | 745 | 75.00
 
 #### Day 5 Greedy
 
@@ -900,6 +906,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0152 |[Maximum Product Subarray](src/main/scala/g0101_0200/s0152_maximum_product_subarray/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 472 | 100.00
 
 #### Day 14 Sliding Window/Two Pointer
 
@@ -948,6 +955,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0136 |[Single Number](src/main/scala/g0101_0200/s0136_single_number/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) | 530 | 78.57
 
 #### Udemy Strings
 
@@ -1007,8 +1015,12 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
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 | 0114 |[Flatten Binary Tree to Linked List](src/main/scala/g0101_0200/s0114_flatten_binary_tree_to_linked_list/Solution.scala)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Big_O_Time_O(N)_Space_O(N) | 491 | 54.17
 | 0024 |[Swap Nodes in Pairs](src/main/scala/g0001_0100/s0024_swap_nodes_in_pairs/Solution.scala)| Medium | Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) | 441 | 95.65
+| 0142 |[Linked List Cycle II](src/main/scala/g0101_0200/s0142_linked_list_cycle_ii/Solution.scala)| Medium | Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) | 501 | 61.54
+| 0141 |[Linked List Cycle](src/main/scala/g0101_0200/s0141_linked_list_cycle/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) | 503 | 84.25
 | 0021 |[Merge Two Sorted Lists](src/main/scala/g0001_0100/s0021_merge_two_sorted_lists/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) | 480 | 89.72
+| 0138 |[Copy List with Random Pointer](src/main/scala/g0101_0200/s0138_copy_list_with_random_pointer/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Big_O_Time_O(N)_Space_O(N) | 477 | 96.00
 | 0025 |[Reverse Nodes in k-Group](src/main/scala/g0001_0100/s0025_reverse_nodes_in_k_group/Solution.scala)| Hard | Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k) | 520 | 80.00
+| 0146 |[LRU Cache](src/main/scala/g0101_0200/s0146_lru_cache/LRUCache.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Design, Linked_List, Doubly_Linked_List, Big_O_Time_O(1)_Space_O(capacity) | 1590 | 85.19
 
 #### Udemy Tree Stack Queue
 
@@ -1034,6 +1046,8 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0139 |[Word Break](src/main/scala/g0101_0200/s0139_word_break/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max\*N)_Space_O(M+N+max) | 482 | 66.67
+| 0152 |[Maximum Product Subarray](src/main/scala/g0101_0200/s0152_maximum_product_subarray/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 472 | 100.00
 | 0070 |[Climbing Stairs](src/main/scala/g0001_0100/s0070_climbing_stairs/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) | 369 | 98.32
 | 0064 |[Minimum Path Sum](src/main/scala/g0001_0100/s0064_minimum_path_sum/Solution.scala)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m\*n)_Space_O(m\*n) | 521 | 92.86
 | 0072 |[Edit Distance](src/main/scala/g0001_0100/s0072_edit_distance/Solution.scala)| Hard | Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) | 487 | 100.00
@@ -1099,6 +1113,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0141 |[Linked List Cycle](src/main/scala/g0101_0200/s0141_linked_list_cycle/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) | 503 | 84.25
 | 0021 |[Merge Two Sorted Lists](src/main/scala/g0001_0100/s0021_merge_two_sorted_lists/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) | 480 | 89.72
 
 #### Day 8 Linked List
@@ -1148,6 +1163,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0136 |[Single Number](src/main/scala/g0101_0200/s0136_single_number/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) | 530 | 78.57
 | 0015 |[3Sum](src/main/scala/g0001_0100/s0015_3sum/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n\*log(n))_Space_O(n^2) | 721 | 95.24
 
 #### Day 2 Array
@@ -1200,6 +1216,7 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
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 | 0002 |[Add Two Numbers](src/main/scala/g0001_0100/s0002_add_two_numbers/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) | 571 | 75.12
+| 0142 |[Linked List Cycle II](src/main/scala/g0101_0200/s0142_linked_list_cycle_ii/Solution.scala)| Medium | Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) | 501 | 61.54
 
 #### Day 11 Linked List
 
@@ -1336,11 +1353,22 @@ implementation 'com.github.javadev:leetcode-in-scala:1.0'
 
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+| 0136 |[Single Number](src/main/scala/g0101_0200/s0136_single_number/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) | 530 | 78.57
 
 ## Algorithms
 
 | #    |      Title     | Difficulty  | Tag         | Time, ms | Time, %
 |------|----------------|-------------|-------------|----------|---------
+| 0152 |[Maximum Product Subarray](src/main/scala/g0101_0200/s0152_maximum_product_subarray/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Dynamic_Programming_I_Day_6, Level_2_Day_13_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 472 | 100.00
+| 0148 |[Sort List](src/main/scala/g0101_0200/s0148_sort_list/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Level_2_Day_4_Linked_List, Big_O_Time_O(log(N))_Space_O(log(N)) | 745 | 75.00
+| 0146 |[LRU Cache](src/main/scala/g0101_0200/s0146_lru_cache/LRUCache.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Design, Linked_List, Doubly_Linked_List, Udemy_Linked_List, Big_O_Time_O(1)_Space_O(capacity) | 1590 | 85.19
+| 0142 |[Linked List Cycle II](src/main/scala/g0101_0200/s0142_linked_list_cycle_ii/Solution.scala)| Medium | Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_II_Day_10_Linked_List, Level_1_Day_4_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) | 501 | 61.54
+| 0141 |[Linked List Cycle](src/main/scala/g0101_0200/s0141_linked_list_cycle/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_I_Day_7_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) | 503 | 84.25
+| 0139 |[Word Break](src/main/scala/g0101_0200/s0139_word_break/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Algorithm_II_Day_15_Dynamic_Programming, Dynamic_Programming_I_Day_9, Udemy_Dynamic_Programming, Big_O_Time_O(M+max\*N)_Space_O(M+N+max) | 482 | 66.67
+| 0138 |[Copy List with Random Pointer](src/main/scala/g0101_0200/s0138_copy_list_with_random_pointer/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Programming_Skills_II_Day_14, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) | 477 | 96.00
+| 0136 |[Single Number](src/main/scala/g0101_0200/s0136_single_number/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Data_Structure_II_Day_1_Array, Algorithm_I_Day_14_Bit_Manipulation, Udemy_Integers, Big_O_Time_O(N)_Space_O(1) | 530 | 78.57
+| 0131 |[Palindrome Partitioning](src/main/scala/g0101_0200/s0131_palindrome_partitioning/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(N\*2^N)_Space_O(2^N\*N) | 797 | 100.00
+| 0128 |[Longest Consecutive Sequence](src/main/scala/g0101_0200/s0128_longest_consecutive_sequence/Solution.scala)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Big_O_Time_O(N_log_N)_Space_O(1) | 708 | 100.00
 | 0124 |[Binary Tree Maximum Path Sum](src/main/scala/g0101_0200/s0124_binary_tree_maximum_path_sum/Solution.scala)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N) | 523 | 89.47
 | 0121 |[Best Time to Buy and Sell Stock](src/main/scala/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution.scala)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Data_Structure_I_Day_3_Array, Dynamic_Programming_I_Day_7, Level_1_Day_5_Greedy, Udemy_Arrays, Big_O_Time_O(N)_Space_O(1) | 762 | 98.45
 | 0114 |[Flatten Binary Tree to Linked List](src/main/scala/g0101_0200/s0114_flatten_binary_tree_to_linked_list/Solution.scala)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) | 491 | 54.17

src/main/scala/com_github_leetcode/random/Node.scala

@@ -0,0 +1,43 @@
+package com_github_leetcode.random
+
+class Node(var _value: Int, var _next: Node = null, var _random: Node = null) {
+    var value: Int = _value
+    var next: Node = _next
+    var random: Node = _random
+
+    override def toString: String = {
+        val result = new StringBuilder()
+        result.append("[")
+        result.append(value)
+        if (random == null) {
+            result.append(",null")
+        } else {
+            var randomIndex = 0
+            var curr2 = this
+            while (curr2.next != null && curr2 != random) {
+                randomIndex += 1
+                curr2 = curr2.next
+            }
+            result.append(",").append(randomIndex)
+        }
+        var curr = next
+        while (curr != null) {
+            result.append("],[")
+            result.append(curr.value)
+            if (curr.random == null) {
+                result.append(",null")
+            } else {
+                var randomIndex = 0
+                var curr2 = this
+                while (curr2.next != null && curr2 != curr.random) {
+                    randomIndex += 1
+                    curr2 = curr2.next
+                }
+                result.append(",").append(randomIndex)
+            }
+            curr = curr.next
+        }
+        result.append("]")
+        result.toString()
+    }
+}

src/main/scala/g0101_0200/s0128_longest_consecutive_sequence/Solution.scala

@@ -0,0 +1,29 @@
+package g0101_0200.s0128_longest_consecutive_sequence
+
+// #Medium #Top_100_Liked_Questions #Top_Interview_Questions #Array #Hash_Table #Union_Find
+// #Big_O_Time_O(N_log_N)_Space_O(1) #2023_11_04_Time_708_ms_(100.00%)_Space_71.7_MB_(94.55%)
+
+import scala.util.Sorting.quickSort
+
+object Solution {
+    def longestConsecutive(nums: Array[Int]): Int = {
+        if (nums.isEmpty) {
+            return 0
+        }
+
+        quickSort(nums)
+        var max = Int.MinValue
+        var thisMax = 1
+
+        for (i <- 0 until nums.length - 1) {
+            if (nums(i + 1) == nums(i) + 1) {
+                thisMax += 1
+            } else if (nums(i + 1) != nums(i)) {
+                max = Math.max(max, thisMax)
+                thisMax = 1
+            }
+        }
+
+        Math.max(max, thisMax)
+    }
+}

src/main/scala/g0101_0200/s0128_longest_consecutive_sequence/readme.md

@@ -0,0 +1,26 @@
+128\. Longest Consecutive Sequence
+
+Medium
+
+Given an unsorted array of integers `nums`, return _the length of the longest consecutive elements sequence._
+
+You must write an algorithm that runs in `O(n)` time.
+
+**Example 1:**
+
+**Input:** nums = [100,4,200,1,3,2]
+
+**Output:** 4
+
+**Explanation:** The longest consecutive elements sequence is `[1, 2, 3, 4]`. Therefore its length is 4. 
+
+**Example 2:**
+
+**Input:** nums = [0,3,7,2,5,8,4,6,0,1]
+
+**Output:** 9 
+
+**Constraints:**
+
+*   <code>0 <= nums.length <= 10<sup>5</sup></code>
+*   <code>-10<sup>9</sup> <= nums[i] <= 10<sup>9</sup></code>

src/main/scala/g0101_0200/s0131_palindrome_partitioning/Solution.scala

@@ -0,0 +1,34 @@
+package g0101_0200.s0131_palindrome_partitioning
+
+// #Medium #Top_100_Liked_Questions #Top_Interview_Questions #String #Dynamic_Programming
+// #Backtracking #Big_O_Time_O(N*2^N)_Space_O(2^N*N)
+// #2023_11_04_Time_797_ms_(100.00%)_Space_84.5_MB_(72.73%)
+
+object Solution {
+    def partition(s: String): List[List[String]] = {
+        val res = scala.collection.mutable.ListBuffer[List[String]]()
+        backtracking(res, List.empty[String], s, 0)
+        res.toList
+    }
+
+    private def backtracking(res: scala.collection.mutable.ListBuffer[List[String]], currArr: List[String], s: String, start: Int): Unit = {
+        if (start == s.length) {
+            res += currArr.reverse
+        }
+        for (end <- start until s.length) {
+            if (isPalindrome(s, start, end)) {
+                backtracking(res, s.substring(start, end + 1) :: currArr, s, end + 1)
+            }
+        }
+    }
+
+    private def isPalindrome(s: String, start: Int, end: Int): Boolean = {
+        var left = start
+        var right = end
+        while (left < right && s(left) == s(right)) {
+            left += 1
+            right -= 1
+        }
+        left >= right
+    }
+}

src/main/scala/g0101_0200/s0131_palindrome_partitioning/readme.md

@@ -0,0 +1,24 @@
+131\. Palindrome Partitioning
+
+Medium
+
+Given a string `s`, partition `s` such that every substring of the partition is a **palindrome**. Return all possible palindrome partitioning of `s`.
+
+A **palindrome** string is a string that reads the same backward as forward.
+
+**Example 1:**
+
+**Input:** s = "aab"
+
+**Output:** [["a","a","b"],["aa","b"]] 
+
+**Example 2:**
+
+**Input:** s = "a"
+
+**Output:** [["a"]] 
+
+**Constraints:**
+
+*   `1 <= s.length <= 16`
+*   `s` contains only lowercase English letters.

src/main/scala/g0101_0200/s0136_single_number/Solution.scala

@@ -0,0 +1,11 @@
+package g0101_0200.s0136_single_number
+
+// #Easy #Top_100_Liked_Questions #Top_Interview_Questions #Array #Bit_Manipulation
+// #Data_Structure_II_Day_1_Array #Algorithm_I_Day_14_Bit_Manipulation #Udemy_Integers
+// #Big_O_Time_O(N)_Space_O(1) #2023_11_04_Time_530_ms_(78.57%)_Space_56.1_MB_(44.05%)
+
+object Solution {
+    def singleNumber(nums: Array[Int]): Int = {
+        nums.foldLeft(0)(_ ^ _)
+    }
+}

src/main/scala/g0101_0200/s0136_single_number/readme.md

@@ -0,0 +1,31 @@
+136\. Single Number
+
+Easy
+
+Given a **non-empty** array of integers `nums`, every element appears _twice_ except for one. Find that single one.
+
+You must implement a solution with a linear runtime complexity and use only constant extra space.
+
+**Example 1:**
+
+**Input:** nums = [2,2,1]
+
+**Output:** 1 
+
+**Example 2:**
+
+**Input:** nums = [4,1,2,1,2]
+
+**Output:** 4 
+
+**Example 3:**
+
+**Input:** nums = [1]
+
+**Output:** 1 
+
+**Constraints:**
+
+*   <code>1 <= nums.length <= 3 * 10<sup>4</sup></code>
+*   <code>-3 * 10<sup>4</sup> <= nums[i] <= 3 * 10<sup>4</sup></code>
+*   Each element in the array appears twice except for one element which appears only once.