Added task 341.

Author: javadev

README.md

@@ -479,6 +479,7 @@ implementation 'com.github.javadev:leetcode-in-kotlin:1.6'
 | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
 |-|-|-|-|-|-
 | 0155 |[Min Stack](src.save/main/kotlin/g0101_0200/s0155_min_stack/MinStack.kt)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design | 331 | 84.88
+| 0341 |[Flatten Nested List Iterator](src/main/kotlin/g0301_0400/s0341_flatten_nested_list_iterator/NestedIterator.kt)| Medium | Top_Interview_Questions, Depth_First_Search, Tree, Stack, Design, Queue, Iterator | 210 | 100.00
 
 #### Day 19
 
@@ -1528,7 +1529,7 @@ implementation 'com.github.javadev:leetcode-in-kotlin:1.6'
 
 | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
 |-|-|-|-|-|-
-| 0374 |[Guess Number Higher or Lower](src/main/kotlin/g0301_0400/s0374_guess_number_higher_or_lower/Solution.kt)| Easy | Binary_Search, Interactive, Binary_Search_I_Day_1 | 134 | 94.19
+| 0374 |[Guess Number Higher or Lower](src/main/kotlin/g0301_0400/s0374_guess_number_higher_or_lower/Solution.kt)| Easy | Binary_Search, Interactive | 134 | 94.19
 
 #### Day 2
 
@@ -1640,6 +1641,7 @@ implementation 'com.github.javadev:leetcode-in-kotlin:1.6'
 | 0344 |[Reverse String](src/main/kotlin/g0301_0400/s0344_reverse_string/Solution.kt)| Easy | Top_Interview_Questions, String, Two_Pointers, Recursion, Algorithm_I_Day_4_Two_Pointers, Udemy_Strings | 445 | 69.75
 | 0343 |[Integer Break](src/main/kotlin/g0301_0400/s0343_integer_break/Solution.kt)| Medium | Dynamic_Programming, Math, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_21 | 218 | 63.89
 | 0342 |[Power of Four](src/main/kotlin/g0301_0400/s0342_power_of_four/Solution.kt)| Easy | Math, Bit_Manipulation, Recursion | 150 | 92.11
+| 0341 |[Flatten Nested List Iterator](src/main/kotlin/g0301_0400/s0341_flatten_nested_list_iterator/NestedIterator.kt)| Medium | Top_Interview_Questions, Depth_First_Search, Tree, Stack, Design, Queue, Iterator, Programming_Skills_II_Day_18 | 210 | 100.00
 | 0338 |[Counting Bits](src/main/kotlin/g0301_0400/s0338_counting_bits/Solution.kt)| Easy | Top_100_Liked_Questions, Dynamic_Programming, Bit_Manipulation, Udemy_Bit_Manipulation | 186 | 99.26
 | 0337 |[House Robber III](src/main/kotlin/g0301_0400/s0337_house_robber_iii/Solution.kt)| Medium | Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue | 282 | 84.62
 | 0336 |[Palindrome Pairs](src/main/kotlin/g0301_0400/s0336_palindrome_pairs/Solution.kt)| Hard | Array, String, Hash_Table, Trie | 2451 | 67.33

src/main/kotlin/com_github_leetcode/NestedInteger.kt

@@ -0,0 +1,34 @@
+package com_github_leetcode
+
+class NestedInteger {
+    private var list: MutableList<NestedInteger>? = null
+    private var integer: Int? = null
+
+    constructor() {
+        list = ArrayList()
+    }
+
+    constructor(list: MutableList<NestedInteger>?) {
+        this.list = list
+    }
+
+    constructor(integer: Int?) {
+        this.integer = integer
+    }
+
+    fun isInteger(): Boolean {
+        return integer != null
+    }
+
+    fun getInteger(): Int? {
+        return integer
+    }
+
+    fun getList(): List<NestedInteger>? {
+        return list
+    }
+
+    fun add(nestedInteger: NestedInteger) {
+        list!!.add(nestedInteger)
+    }
+}

src/main/kotlin/g0301_0400/s0341_flatten_nested_list_iterator/NestedIterator.kt

@@ -0,0 +1,64 @@
+package g0301_0400.s0341_flatten_nested_list_iterator
+
+// #Medium #Top_Interview_Questions #Depth_First_Search #Tree #Stack #Design #Queue #Iterator
+// #Programming_Skills_II_Day_18 #2022_11_25_Time_210_ms_(100.00%)_Space_37.6_MB_(100.00%)
+
+import com_github_leetcode.NestedInteger
+
+/*
+ * // This is the interface that allows for creating nested lists.
+ * // You should not implement it, or speculate about its implementation
+ * class NestedInteger {
+ *     // Constructor initializes an empty nested list.
+ *     constructor()
+ *
+ *     // Constructor initializes a single integer.
+ *     constructor(value: Int)
+ *
+ *     // @return true if this NestedInteger holds a single integer, rather than a nested list.
+ *     fun isInteger(): Boolean
+ *
+ *     // @return the single integer that this NestedInteger holds, if it holds a single integer
+ *     // Return null if this NestedInteger holds a nested list
+ *     fun getInteger(): Int?
+ *
+ *     // Set this NestedInteger to hold a single integer.
+ *     fun setInteger(value: Int): Unit
+ *
+ *     // Set this NestedInteger to hold a nested list and adds a nested integer to it.
+ *     fun add(ni: NestedInteger): Unit
+ *
+ *     // @return the nested list that this NestedInteger holds, if it holds a nested list
+ *     // Return null if this NestedInteger holds a single integer
+ *     fun getList(): List<NestedInteger>?
+ * }
+ */
+class NestedIterator(nestedList: List<NestedInteger>) {
+    private var flattenList = mutableListOf<Int>()
+    private var index = 0
+
+    init {
+        flatten(nestedList, flattenList)
+    }
+
+    private fun flatten(nestedList: List<NestedInteger>, flattenList: MutableList<Int>) {
+        nestedList.forEach { nestedInteger ->
+            if (nestedInteger.isInteger()) {
+                flattenList.add(nestedInteger.getInteger()!!)
+            } else {
+                flatten(nestedInteger.getList()!!, flattenList)
+            }
+        }
+    }
+
+    fun next(): Int = flattenList[index++]
+
+    fun hasNext(): Boolean = index < flattenList.size
+}
+
+/*
+ * Your NestedIterator object will be instantiated and called as such:
+ * var obj = NestedIterator(nestedList)
+ * var param_1 = obj.next()
+ * var param_2 = obj.hasNext()
+ */

src/main/kotlin/g0301_0400/s0341_flatten_nested_list_iterator/readme.md

@@ -0,0 +1,42 @@
+341\. Flatten Nested List Iterator
+
+Medium
+
+You are given a nested list of integers `nestedList`. Each element is either an integer or a list whose elements may also be integers or other lists. Implement an iterator to flatten it.
+
+Implement the `NestedIterator` class:
+
+*   `NestedIterator(List<NestedInteger> nestedList)` Initializes the iterator with the nested list `nestedList`.
+*   `int next()` Returns the next integer in the nested list.
+*   `boolean hasNext()` Returns `true` if there are still some integers in the nested list and `false` otherwise.
+
+Your code will be tested with the following pseudocode:
+
+    initialize iterator with nestedList
+    res = []
+    while iterator.hasNext()
+        append iterator.next() to the end of res
+    return res 
+
+If `res` matches the expected flattened list, then your code will be judged as correct.
+
+**Example 1:**
+
+**Input:** nestedList = [[1,1],2,[1,1]]
+
+**Output:** [1,1,2,1,1]
+
+**Explanation:** By calling next repeatedly until hasNext returns false, the order of elements returned by next should be: [1,1,2,1,1]. 
+
+**Example 2:**
+
+**Input:** nestedList = [1,[4,[6]]]
+
+**Output:** [1,4,6]
+
+**Explanation:** By calling next repeatedly until hasNext returns false, the order of elements returned by next should be: [1,4,6]. 
+
+**Constraints:**
+
+*   `1 <= nestedList.length <= 500`
+*   The values of the integers in the nested list is in the range <code>[-10<sup>6</sup>, 10<sup>6</sup>]</code>.

src/main/kotlin/g0301_0400/s0371_sum_of_two_integers/Solution.kt

@@ -3,6 +3,7 @@ package g0301_0400.s0371_sum_of_two_integers
 // #Medium #Top_Interview_Questions #Math #Bit_Manipulation #Udemy_Bit_Manipulation
 // #2022_11_22_Time_129_ms_(95.45%)_Space_32.9_MB_(90.91%)
 
+@Suppress("NAME_SHADOWING")
 class Solution {
     fun getSum(a: Int, b: Int): Int {
         var a = a

src/main/kotlin/g0301_0400/s0372_super_pow/Solution.kt

@@ -2,6 +2,7 @@ package g0301_0400.s0372_super_pow
 
 // #Medium #Math #Divide_and_Conquer #2022_11_22_Time_196_ms_(100.00%)_Space_36.9_MB_(100.00%)
 
+@Suppress("NAME_SHADOWING")
 class Solution {
     fun superPow(a: Int, b: IntArray): Int {
         val phi = phi(MOD)

src/main/kotlin/g0301_0400/s0382_linked_list_random_node/Solution.kt

@@ -15,7 +15,7 @@ import java.util.Random
  *     var next: ListNode? = null
  * }
  */
-@Suppress("kotlin:S2245")
+@Suppress("NAME_SHADOWING", "kotlin:S2245")
 class Solution(head: ListNode?) {
     private val al: MutableList<Int>
     private val rand: Random

src/test/kotlin/g0301_0400/s0341_flatten_nested_list_iterator/NestedIteratorTest.kt

@@ -0,0 +1,53 @@
+package g0301_0400.s0341_flatten_nested_list_iterator
+
+import com_github_leetcode.NestedInteger
+import org.hamcrest.CoreMatchers.equalTo
+import org.hamcrest.MatcherAssert.assertThat
+import org.junit.jupiter.api.Test
+
+internal class NestedIteratorTest {
+    @Test
+    fun nestedIterator() {
+        val iterator = NestedIterator(
+            mutableListOf(
+                NestedInteger(
+                    mutableListOf(NestedInteger(1), NestedInteger(1))
+                ),
+                NestedInteger(2),
+                NestedInteger(
+                    mutableListOf(
+                        NestedInteger(1), NestedInteger(1)
+                    )
+                )
+            )
+        )
+        val result: MutableList<Int> = ArrayList()
+        while (iterator.hasNext()) {
+            result.add(iterator.next())
+        }
+        assertThat(result, equalTo(listOf(1, 1, 2, 1, 1)))
+    }
+
+    @Test
+    fun nestedIterator2() {
+        val integer1 = NestedInteger(1)
+        val integer2 = NestedInteger(2)
+        val integer3 = NestedInteger(3)
+        val list: MutableList<NestedInteger> = ArrayList()
+        list.add(integer1)
+        list.add(integer2)
+        list.add(integer3)
+        val nestedIntegerList = NestedInteger(list)
+        val input: MutableList<NestedInteger> = ArrayList()
+        input.add(integer1)
+        input.add(integer2)
+        input.add(nestedIntegerList)
+        input.add(integer3)
+        val iterator = NestedIterator(input)
+        val result: MutableList<Int> = ArrayList()
+        while (iterator.hasNext()) {
+            result.add(iterator.next())
+        }
+        assertThat(result, equalTo(listOf(1, 2, 1, 2, 3, 3)))
+    }
+}