Improved tasks 3394, 3395, 3396, 3399, 3404

src/main/kotlin/g3301_3400/s3394_check_if_grid_can_be_cut_into_sections/Solution.kt

@@ -8,8 +8,8 @@ import kotlin.math.max
 class Solution {
     fun checkValidCuts(n: Int, rectangles: Array<IntArray>): Boolean {
         val m = rectangles.size
-        val xAxis = Array<IntArray?>(m) { IntArray(2) }
-        val yAxis = Array<IntArray?>(m) { IntArray(2) }
+        val xAxis = Array<IntArray>(m) { IntArray(2) }
+        val yAxis = Array<IntArray>(m) { IntArray(2) }
         var ind = 0
         for (axis in rectangles) {
             val startX = axis[0]
@@ -21,8 +21,8 @@ class Solution {
             ind++
         }
 
-        xAxis.sortWith<IntArray?>(
-            Comparator { a: IntArray?, b: IntArray? -> if (a!![0] == b!![0]) a[1] - b[1] else a[0] - b[0] },
+        xAxis.sortWith<IntArray>(
+            Comparator { a: IntArray, b: IntArray -> if (a[0] == b[0]) a[1] - b[1] else a[0] - b[0] },
         )
 
         yAxis.sortWith<IntArray?>(
@@ -36,15 +36,15 @@ class Solution {
         return horizontalCuts > 2
     }
 
-    private fun findSections(axis: Array<IntArray?>): Int {
-        var end = axis[0]!![1]
+    private fun findSections(axis: Array<IntArray>): Int {
+        var end = axis[0][1]
         var sections = 1
         for (i in 1..<axis.size) {
-            if (end > axis[i]!![0]) {
-                end = max(end, axis[i]!![1])
+            if (end > axis[i][0]) {
+                end = max(end, axis[i][1])
             } else {
                 sections++
-                end = axis[i]!![1]
+                end = axis[i][1]
             }
             if (sections > 2) {
                 return sections

src/main/kotlin/g3301_3400/s3395_subsequences_with_a_unique_middle_mode_i/Solution.kt

@@ -6,17 +6,17 @@ class Solution {
     fun subsequencesWithMiddleMode(a: IntArray): Int {
         val n = a.size
         // Create a dictionary to store indices of each number
-        val dict: MutableMap<Int?, MutableList<Int?>?> = HashMap<Int?, MutableList<Int?>?>()
+        val dict: MutableMap<Int, MutableList<Int>> = HashMap()
         for (i in 0..<n) {
-            dict.computeIfAbsent(a[i]) { _: Int? -> java.util.ArrayList<Int?>() }!!.add(i)
+            dict.computeIfAbsent(a[i]) { _: Int -> ArrayList<Int>() }.add(i)
         }
         var ans = 0L
         // Iterate over each unique number and its indices
         for (entry in dict.entries) {
-            val b: MutableList<Int?> = entry.value!!
+            val b: MutableList<Int> = entry.value
             val m = b.size
             for (k in 0..<m) {
-                val i: Int = b[k]!!
+                val i: Int = b[k]
                 val r = m - 1 - k
                 val u = i - k
                 val v = (n - 1 - i) - r
@@ -71,20 +71,20 @@ class Solution {
         var dif: Long = 0
         // Principle of inclusion-exclusion
         for (midEntry in dict.entries) {
-            val b: MutableList<Int?> = midEntry.value!!
+            val b: MutableList<Int> = midEntry.value
             val m = b.size
             for (tmpEntry in dict.entries) {
                 if (midEntry.key != tmpEntry.key) {
-                    val c: MutableList<Int?> = tmpEntry.value!!
+                    val c: MutableList<Int> = tmpEntry.value
                     val size = c.size
                     var k = 0
                     var j = 0
                     while (k < m) {
-                        val i: Int = b[k]!!
+                        val i: Int = b[k]
                         val r = m - 1 - k
                         val u = i - k
                         val v = (n - 1 - i) - r
-                        while (j < size && c[j]!! < i) {
+                        while (j < size && c[j] < i) {
                             j++
                         }
                         val x = j

src/main/kotlin/g3301_3400/s3396_minimum_number_of_operations_to_make_elements_in_array_distinct/Solution.kt

@@ -6,10 +6,10 @@ import kotlin.math.min
 
 class Solution {
     fun minimumOperations(nums: IntArray): Int {
-        val map: MutableMap<Int?, Int?> = HashMap<Int?, Int?>()
+        val map: MutableMap<Int, Int> = HashMap()
         var dupct = 0
         for (num in nums) {
-            map.put(num, map.getOrDefault(num, 0)!! + 1)
+            map.put(num, map.getOrDefault(num, 0) + 1)
             if (map[num] == 2) {
                 dupct++
             }

src/main/kotlin/g3301_3400/s3399_smallest_substring_with_identical_characters_ii/Solution.kt

@@ -24,7 +24,7 @@ class Solution {
         if (flips <= numOps) {
             return 1
         }
-        val seg: MutableList<Int> = ArrayList<Int>()
+        val seg: MutableList<Int> = ArrayList()
         var count = 1
         var max = 1
         for (i in 1..<b.size) {

src/main/kotlin/g3401_3500/s3404_count_special_subsequences/Solution.kt

@@ -4,18 +4,18 @@ package g3401_3500.s3404_count_special_subsequences
 
 class Solution {
     fun numberOfSubsequences(nums: IntArray): Long {
-        val freq: MutableMap<Double?, Int?> = HashMap<Double?, Int?>()
+        val freq: MutableMap<Double, Int> = HashMap()
         var ans: Long = 0
         for (r in 4..<nums.size) {
             var p = 0
             val q = r - 2
             while (p < q - 1) {
                 val key = nums[p].toDouble() / nums[q]
-                freq.put(key, freq.getOrDefault(key, 0)!! + 1)
+                freq.put(key, freq.getOrDefault(key, 0) + 1)
                 ++p
             }
             for (s in r + 2..<nums.size) {
-                ans += freq.getOrDefault(nums[s].toDouble() / nums[r], 0)!!.toLong()
+                ans += freq.getOrDefault(nums[s].toDouble() / nums[r], 0).toLong()
             }
         }
         return ans