diff --git a/README.md b/README.md
index a96cea94..cf815b4e 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,6 @@
 [![](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)
 > ["For coding interview preparation, LeetCode is one of the best online resource providing a rich library of more than 300 real coding interview questions for you to practice from using one of the 7 supported languages - C, C++, Java, Python, C#, JavaScript, Ruby."](https://www.quora.com/How-effective-is-Leetcode-for-preparing-for-technical-interviews)
 
-* [Programming Skills I](#programming-skills-i)
 * [Programming Skills II](#programming-skills-ii)
 * [Graph Theory I](#graph-theory-i)
 * [SQL I](#sql-i)
@@ -16,102 +15,7 @@
 * [Binary Search I](#binary-search-i)
 * [Binary Search II](#binary-search-ii)
 * [Dynamic Programming I](#dynamic-programming-i)
-
-### Programming Skills I
-
-#### Day 1 Basic Data Type
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1523 |[Count Odd Numbers in an Interval Range](src/main/kotlin/g1501_1600/s1523_count_odd_numbers_in_an_interval_range)| Easy | Math | 114 | 97.22
-| 1491 |[Average Salary Excluding the Minimum and Maximum Salary](src/main/kotlin/g1401_1500/s1491_average_salary_excluding_the_minimum_and_maximum_salary)| Easy | Array, Sorting | 165 | 27.87
-
-#### Day 2 Operator
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 0191 |[Number of 1 Bits](src/main/kotlin/g0101_0200/s0191_number_of_1_bits)| Easy | Top_Interview_Questions, Bit_Manipulation | 237 | 68.44
-| 1281 |[Subtract the Product and Sum of Digits of an Integer](src/main/kotlin/g1201_1300/s1281_subtract_the_product_and_sum_of_digits_of_an_integer)| Easy | Math | 128 | 61.82
-
-#### Day 3 Conditional Statements
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 0976 |[Largest Perimeter Triangle](src/main/kotlin/g0901_1000/s0976_largest_perimeter_triangle)| Easy | Array, Math, Sorting, Greedy | 304 | 33.33
-| 1779 |[Find Nearest Point That Has the Same X or Y Coordinate](src/main/kotlin/g1701_1800/s1779_find_nearest_point_that_has_the_same_x_or_y_coordinate)| Easy | Array | 364 | 100.00
-
-#### Day 4 Loop
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1822 |[Sign of the Product of an Array](src/main/kotlin/g1801_1900/s1822_sign_of_the_product_of_an_array)| Easy | Array, Math | 170 | 92.51
-| 1502 |[Can Make Arithmetic Progression From Sequence](src/main/kotlin/g1501_1600/s1502_can_make_arithmetic_progression_from_sequence)| Easy | Array, Sorting | 156 | 94.82
-| 0202 |[Happy Number](src/main/kotlin/g0201_0300/s0202_happy_number)| Easy | Top_Interview_Questions, Hash_Table, Math, Two_Pointers | 261 | 45.08
-| 1790 |[Check if One String Swap Can Make Strings Equal](src/main/kotlin/g1701_1800/s1790_check_if_one_string_swap_can_make_strings_equal)| Easy | String, Hash_Table, Counting | 138 | 100.00
-
-#### Day 5 Function
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 0589 |[N-ary Tree Preorder Traversal](src/main/kotlin/g0501_0600/s0589_n_ary_tree_preorder_traversal)| Easy | Depth_First_Search, Tree, Stack | 233 | 84.02
-| 0496 |[Next Greater Element I](src/main/kotlin/g0401_0500/s0496_next_greater_element_i)| Easy | Array, Hash_Table, Stack, Monotonic_Stack | 171 | 100.00
-| 1232 |[Check If It Is a Straight Line](src/main/kotlin/g1201_1300/s1232_check_if_it_is_a_straight_line)| Easy | Array, Math, Geometry | 152 | 95.38
-
-#### Day 6 Array
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1588 |[Sum of All Odd Length Subarrays](src/main/kotlin/g1501_1600/s1588_sum_of_all_odd_length_subarrays)| Easy | Array, Math, Prefix_Sum | 157 | 64.00
-| 0283 |[Move Zeroes](src/main/kotlin/g0201_0300/s0283_move_zeroes)| Easy | Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 516 | 79.07
-| 1672 |[Richest Customer Wealth](src/main/kotlin/g1601_1700/s1672_richest_customer_wealth)| Easy | Array, Matrix | 155 | 94.54
-
-#### Day 7 Array
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1572 |[Matrix Diagonal Sum](src/main/kotlin/g1501_1600/s1572_matrix_diagonal_sum)| Easy | Array, Matrix | 221 | 67.61
-| 0566 |[Reshape the Matrix](src/main/kotlin/g0501_0600/s0566_reshape_the_matrix)| Easy | Array, Matrix, Simulation | 239 | 99.05
-
-#### Day 8 String
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1768 |[Merge Strings Alternately](src/main/kotlin/g1701_1800/s1768_merge_strings_alternately)| Easy | String, Two_Pointers | 138 | 93.81
-| 1678 |[Goal Parser Interpretation](src/main/kotlin/g1601_1700/s1678_goal_parser_interpretation)| Easy | String | 136 | 88.24
-| 0389 |[Find the Difference](src/main/kotlin/g0301_0400/s0389_find_the_difference)| Easy | String, Hash_Table, Sorting, Bit_Manipulation | 256 | 64.81
-
-#### Day 9 String
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 0709 |[To Lower Case](src/main/kotlin/g0701_0800/s0709_to_lower_case)| Easy | String | 142 | 98.68
-| 1309 |[Decrypt String from Alphabet to Integer Mapping](src/main/kotlin/g1301_1400/s1309_decrypt_string_from_alphabet_to_integer_mapping)| Easy | String | 129 | 95.45
-| 0953 |[Verifying an Alien Dictionary](src/main/kotlin/g0901_1000/s0953_verifying_an_alien_dictionary)| Easy | Array, String, Hash_Table | 137 | 100.00
-
-#### Day 10 Linked List and Tree
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1290 |[Convert Binary Number in a Linked List to Integer](src/main/kotlin/g1201_1300/s1290_convert_binary_number_in_a_linked_list_to_integer)| Easy | Math, Linked_List | 145 | 25.93
-| 0876 |[Middle of the Linked List](src/main/kotlin/g0801_0900/s0876_middle_of_the_linked_list)| Easy | Two_Pointers, Linked_List | 136 | 76.52
-| 0104 |[Maximum Depth of Binary Tree](src/main/kotlin/g0101_0200/s0104_maximum_depth_of_binary_tree)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) | 166 | 83.53
-| 0404 |[Sum of Left Leaves](src/main/kotlin/g0401_0500/s0404_sum_of_left_leaves)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree | 173 | 86.05
-
-#### Day 11 Containers and Libraries
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1356 |[Sort Integers by The Number of 1 Bits](src/main/kotlin/g1301_1400/s1356_sort_integers_by_the_number_of_1_bits)| Easy | Array, Sorting, Bit_Manipulation, Counting | 236 | 92.31
-| 0232 |[Implement Queue using Stacks](src/main/kotlin/g0201_0300/s0232_implement_queue_using_stacks)| Easy | Stack, Design, Queue | 258 | 70.86
-| 0242 |[Valid Anagram](src/main/kotlin/g0201_0300/s0242_valid_anagram)| Easy | String, Hash_Table, Sorting | 251 | 87.65
-| 0217 |[Contains Duplicate](src/main/kotlin/g0201_0300/s0217_contains_duplicate)| Easy | Top_Interview_Questions, Array, Hash_Table, Sorting | 719 | 73.49
-
-#### Day 12 Class and Object
-
-| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
-|-|-|-|-|-|-
-| 1603 |[Design Parking System](src/main/kotlin/g1601_1700/s1603_design_parking_system)| Easy | Design, Simulation, Counting | 376 | 31.83
-| 0303 |[Range Sum Query - Immutable](src/main/kotlin/g0301_0400/s0303_range_sum_query_immutable)| Easy | Array, Design, Prefix_Sum | 472 | 63.64
+* [Programming Skills I](#programming-skills-i)
 
 ### Programming Skills II
 
@@ -1812,6 +1716,102 @@
 | 0343 |[Integer Break](src/main/kotlin/g0301_0400/s0343_integer_break)| Medium | Dynamic_Programming, Math | 218 | 63.89
 | 0279 |[Perfect Squares](src/main/kotlin/g0201_0300/s0279_perfect_squares)| Medium | Dynamic_Programming, Math, Breadth_First_Search | 176 | 98.80
 
+### Programming Skills I
+
+#### Day 1 Basic Data Type
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1523 |[Count Odd Numbers in an Interval Range](src/main/kotlin/g1501_1600/s1523_count_odd_numbers_in_an_interval_range)| Easy | Math | 114 | 97.22
+| 1491 |[Average Salary Excluding the Minimum and Maximum Salary](src/main/kotlin/g1401_1500/s1491_average_salary_excluding_the_minimum_and_maximum_salary)| Easy | Array, Sorting | 165 | 27.87
+
+#### Day 2 Operator
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 0191 |[Number of 1 Bits](src/main/kotlin/g0101_0200/s0191_number_of_1_bits)| Easy | Top_Interview_Questions, Bit_Manipulation | 237 | 68.44
+| 1281 |[Subtract the Product and Sum of Digits of an Integer](src/main/kotlin/g1201_1300/s1281_subtract_the_product_and_sum_of_digits_of_an_integer)| Easy | Math | 128 | 61.82
+
+#### Day 3 Conditional Statements
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 0976 |[Largest Perimeter Triangle](src/main/kotlin/g0901_1000/s0976_largest_perimeter_triangle)| Easy | Array, Math, Sorting, Greedy | 304 | 33.33
+| 1779 |[Find Nearest Point That Has the Same X or Y Coordinate](src/main/kotlin/g1701_1800/s1779_find_nearest_point_that_has_the_same_x_or_y_coordinate)| Easy | Array | 364 | 100.00
+
+#### Day 4 Loop
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1822 |[Sign of the Product of an Array](src/main/kotlin/g1801_1900/s1822_sign_of_the_product_of_an_array)| Easy | Array, Math | 170 | 92.51
+| 1502 |[Can Make Arithmetic Progression From Sequence](src/main/kotlin/g1501_1600/s1502_can_make_arithmetic_progression_from_sequence)| Easy | Array, Sorting | 156 | 94.82
+| 0202 |[Happy Number](src/main/kotlin/g0201_0300/s0202_happy_number)| Easy | Top_Interview_Questions, Hash_Table, Math, Two_Pointers | 261 | 45.08
+| 1790 |[Check if One String Swap Can Make Strings Equal](src/main/kotlin/g1701_1800/s1790_check_if_one_string_swap_can_make_strings_equal)| Easy | String, Hash_Table, Counting | 138 | 100.00
+
+#### Day 5 Function
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 0589 |[N-ary Tree Preorder Traversal](src/main/kotlin/g0501_0600/s0589_n_ary_tree_preorder_traversal)| Easy | Depth_First_Search, Tree, Stack | 233 | 84.02
+| 0496 |[Next Greater Element I](src/main/kotlin/g0401_0500/s0496_next_greater_element_i)| Easy | Array, Hash_Table, Stack, Monotonic_Stack | 171 | 100.00
+| 1232 |[Check If It Is a Straight Line](src/main/kotlin/g1201_1300/s1232_check_if_it_is_a_straight_line)| Easy | Array, Math, Geometry | 152 | 95.38
+
+#### Day 6 Array
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1588 |[Sum of All Odd Length Subarrays](src/main/kotlin/g1501_1600/s1588_sum_of_all_odd_length_subarrays)| Easy | Array, Math, Prefix_Sum | 157 | 64.00
+| 0283 |[Move Zeroes](src/main/kotlin/g0201_0300/s0283_move_zeroes)| Easy | Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 516 | 79.07
+| 1672 |[Richest Customer Wealth](src/main/kotlin/g1601_1700/s1672_richest_customer_wealth)| Easy | Array, Matrix | 155 | 94.54
+
+#### Day 7 Array
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1572 |[Matrix Diagonal Sum](src/main/kotlin/g1501_1600/s1572_matrix_diagonal_sum)| Easy | Array, Matrix | 221 | 67.61
+| 0566 |[Reshape the Matrix](src/main/kotlin/g0501_0600/s0566_reshape_the_matrix)| Easy | Array, Matrix, Simulation | 239 | 99.05
+
+#### Day 8 String
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1768 |[Merge Strings Alternately](src/main/kotlin/g1701_1800/s1768_merge_strings_alternately)| Easy | String, Two_Pointers | 138 | 93.81
+| 1678 |[Goal Parser Interpretation](src/main/kotlin/g1601_1700/s1678_goal_parser_interpretation)| Easy | String | 136 | 88.24
+| 0389 |[Find the Difference](src/main/kotlin/g0301_0400/s0389_find_the_difference)| Easy | String, Hash_Table, Sorting, Bit_Manipulation | 256 | 64.81
+
+#### Day 9 String
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 0709 |[To Lower Case](src/main/kotlin/g0701_0800/s0709_to_lower_case)| Easy | String | 142 | 98.68
+| 1309 |[Decrypt String from Alphabet to Integer Mapping](src/main/kotlin/g1301_1400/s1309_decrypt_string_from_alphabet_to_integer_mapping)| Easy | String | 129 | 95.45
+| 0953 |[Verifying an Alien Dictionary](src/main/kotlin/g0901_1000/s0953_verifying_an_alien_dictionary)| Easy | Array, String, Hash_Table | 137 | 100.00
+
+#### Day 10 Linked List and Tree
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1290 |[Convert Binary Number in a Linked List to Integer](src/main/kotlin/g1201_1300/s1290_convert_binary_number_in_a_linked_list_to_integer)| Easy | Math, Linked_List | 145 | 25.93
+| 0876 |[Middle of the Linked List](src/main/kotlin/g0801_0900/s0876_middle_of_the_linked_list)| Easy | Two_Pointers, Linked_List | 136 | 76.52
+| 0104 |[Maximum Depth of Binary Tree](src/main/kotlin/g0101_0200/s0104_maximum_depth_of_binary_tree)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) | 166 | 83.53
+| 0404 |[Sum of Left Leaves](src/main/kotlin/g0401_0500/s0404_sum_of_left_leaves)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree | 173 | 86.05
+
+#### Day 11 Containers and Libraries
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1356 |[Sort Integers by The Number of 1 Bits](src/main/kotlin/g1301_1400/s1356_sort_integers_by_the_number_of_1_bits)| Easy | Array, Sorting, Bit_Manipulation, Counting | 236 | 92.31
+| 0232 |[Implement Queue using Stacks](src/main/kotlin/g0201_0300/s0232_implement_queue_using_stacks)| Easy | Stack, Design, Queue | 258 | 70.86
+| 0242 |[Valid Anagram](src/main/kotlin/g0201_0300/s0242_valid_anagram)| Easy | String, Hash_Table, Sorting | 251 | 87.65
+| 0217 |[Contains Duplicate](src/main/kotlin/g0201_0300/s0217_contains_duplicate)| Easy | Top_Interview_Questions, Array, Hash_Table, Sorting | 719 | 73.49
+
+#### Day 12 Class and Object
+
+| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
+|-|-|-|-|-|-
+| 1603 |[Design Parking System](src/main/kotlin/g1601_1700/s1603_design_parking_system)| Easy | Design, Simulation, Counting | 376 | 31.83
+| 0303 |[Range Sum Query - Immutable](src/main/kotlin/g0301_0400/s0303_range_sum_query_immutable)| Easy | Array, Design, Prefix_Sum | 472 | 63.64
+
 ## Algorithms
 
 | #    |      Title     | Difficulty  | Tag         | Time, ms | Time, %
diff --git a/src/main/kotlin/g0901_1000/s0939_minimum_area_rectangle/readme.md b/src/main/kotlin/g0901_1000/s0939_minimum_area_rectangle/readme.md
index eaf14e24..b0b13dfd 100644
--- a/src/main/kotlin/g0901_1000/s0939_minimum_area_rectangle/readme.md
+++ b/src/main/kotlin/g0901_1000/s0939_minimum_area_rectangle/readme.md
@@ -35,7 +35,6 @@ Return _the minimum area of a rectangle formed from these points, with sides par
 ## Solution
 
 ```kotlin
-import java.util.Arrays
 import kotlin.math.abs
 
 class Solution {
@@ -48,9 +47,7 @@ class Solution {
             map.putIfAbsent(p[0], HashSet())
             map.getValue(p[0]).add(p[1])
         }
-        Arrays.sort(
-            points
-        ) { a: IntArray, b: IntArray ->
+        points.sortWith { a: IntArray, b: IntArray ->
             if (a[0] == b[0]) Integer.compare(
                 a[1],
                 b[1]
diff --git a/src/main/kotlin/g0901_1000/s0956_tallest_billboard/readme.md b/src/main/kotlin/g0901_1000/s0956_tallest_billboard/readme.md
index e6536ad6..89e90bea 100644
--- a/src/main/kotlin/g0901_1000/s0956_tallest_billboard/readme.md
+++ b/src/main/kotlin/g0901_1000/s0956_tallest_billboard/readme.md
@@ -44,8 +44,6 @@ Return _the largest possible height of your billboard installation_. If you cann
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     fun tallestBillboard(rods: IntArray): Int {
         var maxDiff = 0
@@ -53,7 +51,7 @@ class Solution {
             maxDiff += rod
         }
         val dp = IntArray(maxDiff + 1)
-        Arrays.fill(dp, -1)
+        dp.fill(-1)
         dp[0] = 0
         for (l in rods) {
             val dpOld = IntArray(maxDiff + 1)
diff --git a/src/main/kotlin/g0901_1000/s0957_prison_cells_after_n_days/readme.md b/src/main/kotlin/g0901_1000/s0957_prison_cells_after_n_days/readme.md
index 96124ec1..1c43d1be 100644
--- a/src/main/kotlin/g0901_1000/s0957_prison_cells_after_n_days/readme.md
+++ b/src/main/kotlin/g0901_1000/s0957_prison_cells_after_n_days/readme.md
@@ -57,8 +57,6 @@ Day 7: [0, 0, 1, 1, 0, 0, 0, 0]
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 @Suppress("NAME_SHADOWING")
 class Solution {
     fun prisonAfterNDays(cells: IntArray, n: Int): IntArray {
@@ -74,7 +72,7 @@ class Solution {
             day++
             n--
             val next = getNextDay(prev)
-            if (Arrays.equals(next, first)) {
+            if (next.contentEquals(first)) {
                 period = day - 1
                 n %= period
             }
diff --git a/src/main/kotlin/g1001_1100/s1024_video_stitching/readme.md b/src/main/kotlin/g1001_1100/s1024_video_stitching/readme.md
index 7eed100b..91140fb1 100644
--- a/src/main/kotlin/g1001_1100/s1024_video_stitching/readme.md
+++ b/src/main/kotlin/g1001_1100/s1024_video_stitching/readme.md
@@ -54,11 +54,9 @@ Now we have segments [0,2] + [2,8] + [8,10] which cover the sporting event [0, 1
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     fun videoStitching(clips: Array<IntArray>, time: Int): Int {
-        Arrays.sort(clips) { a: IntArray, b: IntArray ->
+        clips.sortWith { a: IntArray, b: IntArray ->
             if (a[0] == b[0]
             ) a[1] - b[1] else a[0] - b[0]
         }
diff --git a/src/main/kotlin/g1001_1100/s1027_longest_arithmetic_subsequence/readme.md b/src/main/kotlin/g1001_1100/s1027_longest_arithmetic_subsequence/readme.md
index 104ed748..7e9f0fa7 100644
--- a/src/main/kotlin/g1001_1100/s1027_longest_arithmetic_subsequence/readme.md
+++ b/src/main/kotlin/g1001_1100/s1027_longest_arithmetic_subsequence/readme.md
@@ -38,8 +38,6 @@ Given an array `nums` of integers, return _the length of the longest arithmetic
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     fun longestArithSeqLength(nums: IntArray): Int {
         val max = maxElement(nums)
@@ -48,7 +46,7 @@ class Solution {
         val n = nums.size
         val dp = Array(n) { IntArray(2 * diff + 2) }
         for (d in dp) {
-            Arrays.fill(d, 1)
+            d.fill(1)
         }
         var ans = 0
         for (i in 0 until n) {
diff --git a/src/main/kotlin/g1001_1100/s1029_two_city_scheduling/readme.md b/src/main/kotlin/g1001_1100/s1029_two_city_scheduling/readme.md
index cc22f8e7..250e2285 100644
--- a/src/main/kotlin/g1001_1100/s1029_two_city_scheduling/readme.md
+++ b/src/main/kotlin/g1001_1100/s1029_two_city_scheduling/readme.md
@@ -49,11 +49,9 @@ The total minimum cost is 10 + 30 + 50 + 20 = 110 to have half the people interv
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     fun twoCitySchedCost(costs: Array<IntArray>): Int {
-        Arrays.sort(costs) { a: IntArray, b: IntArray ->
+        costs.sortWith { a: IntArray, b: IntArray ->
             a[0] - a[1] - (b[0] - b[1])
         }
         var cost = 0
diff --git a/src/main/kotlin/g1001_1100/s1081_smallest_subsequence_of_distinct_characters/readme.md b/src/main/kotlin/g1001_1100/s1081_smallest_subsequence_of_distinct_characters/readme.md
index 59b47146..9b05b620 100644
--- a/src/main/kotlin/g1001_1100/s1081_smallest_subsequence_of_distinct_characters/readme.md
+++ b/src/main/kotlin/g1001_1100/s1081_smallest_subsequence_of_distinct_characters/readme.md
@@ -29,7 +29,6 @@ Given a string `s`, return _the_ _lexicographically smallest_ _subsequence_ _of_
 ## Solution
 
 ```kotlin
-import java.util.Arrays
 import java.util.Deque
 import java.util.LinkedList
 
@@ -39,7 +38,7 @@ class Solution {
         val stk: Deque<Char> = LinkedList()
         val freq = IntArray(26)
         val exist = BooleanArray(26)
-        Arrays.fill(exist, false)
+        exist.fill(false)
         for (ch in s.toCharArray()) {
             freq[ch.code - 'a'.code]++
         }
diff --git a/src/main/kotlin/g1201_1300/s1235_maximum_profit_in_job_scheduling/readme.md b/src/main/kotlin/g1201_1300/s1235_maximum_profit_in_job_scheduling/readme.md
index ee7229d1..1e891e5c 100644
--- a/src/main/kotlin/g1201_1300/s1235_maximum_profit_in_job_scheduling/readme.md
+++ b/src/main/kotlin/g1201_1300/s1235_maximum_profit_in_job_scheduling/readme.md
@@ -48,8 +48,6 @@ If you choose a job that ends at time `X` you will be able to start another job
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     fun jobScheduling(startTime: IntArray, endTime: IntArray, profit: IntArray): Int {
         val n = startTime.size
@@ -59,7 +57,7 @@ class Solution {
             time[i][1] = endTime[i]
             time[i][2] = profit[i]
         }
-        Arrays.sort(time, { a: IntArray, b: IntArray -> a[1].compareTo(b[1]) })
+        time.sortWith { a: IntArray, b: IntArray -> a[1].compareTo(b[1]) }
         val maxP = Array(n) { IntArray(2) }
         var lastPos = -1
         var currProfit: Int
diff --git a/src/main/kotlin/g1301_1400/s1353_maximum_number_of_events_that_can_be_attended/readme.md b/src/main/kotlin/g1301_1400/s1353_maximum_number_of_events_that_can_be_attended/readme.md
index cbd5c893..3b794d06 100644
--- a/src/main/kotlin/g1301_1400/s1353_maximum_number_of_events_that_can_be_attended/readme.md
+++ b/src/main/kotlin/g1301_1400/s1353_maximum_number_of_events_that_can_be_attended/readme.md
@@ -44,12 +44,11 @@ Attend the third event on day 3.
 ## Solution
 
 ```kotlin
-import java.util.Arrays
 import java.util.PriorityQueue
 
 class Solution {
     fun maxEvents(events: Array<IntArray>): Int {
-        Arrays.sort(events) { a: IntArray, b: IntArray -> a[0] - b[0] }
+        events.sortWith { a: IntArray, b: IntArray -> a[0] - b[0] }
         var ans = 0
         var i = 0
         val pq = PriorityQueue<Int>()
diff --git a/src/main/kotlin/g1301_1400/s1366_rank_teams_by_votes/readme.md b/src/main/kotlin/g1301_1400/s1366_rank_teams_by_votes/readme.md
index d74c8d55..7cd1e90a 100644
--- a/src/main/kotlin/g1301_1400/s1366_rank_teams_by_votes/readme.md
+++ b/src/main/kotlin/g1301_1400/s1366_rank_teams_by_votes/readme.md
@@ -55,8 +55,6 @@ As most of the voters ranked C second, team C is the second team and team B is t
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     internal class Node(var c: Char) {
         var count = IntArray(26)
@@ -72,9 +70,8 @@ class Solution {
                 nodes[vote[i].code - 'A'.code]!!.count[i]++
             }
         }
-        Arrays.sort(
-            nodes
-        ) { o1: Node?, o2: Node? ->
+
+        nodes.sortWith sort@{ o1: Node?, o2: Node? ->
             for (i in 0..25) {
                 if (o1!!.count[i] != o2!!.count[i]) {
                     return@sort o2.count[i] - o1.count[i]
diff --git a/src/main/kotlin/g1301_1400/s1383_maximum_performance_of_a_team/readme.md b/src/main/kotlin/g1301_1400/s1383_maximum_performance_of_a_team/readme.md
index 2acec6a5..180d73a7 100644
--- a/src/main/kotlin/g1301_1400/s1383_maximum_performance_of_a_team/readme.md
+++ b/src/main/kotlin/g1301_1400/s1383_maximum_performance_of_a_team/readme.md
@@ -50,7 +50,6 @@ This is the same example as the first but k = 3. We can select engineer 1, engin
 ## Solution
 
 ```kotlin
-import java.util.Arrays
 import java.util.PriorityQueue
 
 class Solution {
@@ -60,7 +59,7 @@ class Solution {
             engineers[i][0] = speed[i]
             engineers[i][1] = efficiency[i]
         }
-        Arrays.sort(engineers) { engineer1: IntArray, engineer2: IntArray -> engineer2[1] - engineer1[1] }
+        engineers.sortWith { engineer1: IntArray, engineer2: IntArray -> engineer2[1] - engineer1[1] }
         var speedSum: Long = 0
         var maximumPerformance: Long = 0
         val minHeap = PriorityQueue<Int>()
diff --git a/src/main/kotlin/g1301_1400/s1387_sort_integers_by_the_power_value/readme.md b/src/main/kotlin/g1301_1400/s1387_sort_integers_by_the_power_value/readme.md
index 00fd7d05..d6306277 100644
--- a/src/main/kotlin/g1301_1400/s1387_sort_integers_by_the_power_value/readme.md
+++ b/src/main/kotlin/g1301_1400/s1387_sort_integers_by_the_power_value/readme.md
@@ -56,8 +56,6 @@ The fourth number in the sorted array is 7.
 ## Solution
 
 ```kotlin
-import java.util.Arrays
-
 class Solution {
     private lateinit var cacheMap: MutableMap<Int, Int>
 
@@ -69,7 +67,7 @@ class Solution {
             arr[i][0] = lo + i
             arr[i][1] = getStepCount(lo + i)
         }
-        Arrays.sort(arr) { a: IntArray, b: IntArray -> a[1].compareTo(b[1]) }
+        arr.sortWith { a: IntArray, b: IntArray -> a[1].compareTo(b[1]) }
         return arr[k - 1][0]
     }
 
diff --git a/src/main/kotlin/g1401_1500/s1489_find_critical_and_pseudo_critical_edges_in_minimum_spanning_tree/readme.md b/src/main/kotlin/g1401_1500/s1489_find_critical_and_pseudo_critical_edges_in_minimum_spanning_tree/readme.md
index 168dcf46..893f5361 100644
--- a/src/main/kotlin/g1401_1500/s1489_find_critical_and_pseudo_critical_edges_in_minimum_spanning_tree/readme.md
+++ b/src/main/kotlin/g1401_1500/s1489_find_critical_and_pseudo_critical_edges_in_minimum_spanning_tree/readme.md
@@ -51,7 +51,6 @@ The edges 2, 3, 4, and 5 are only part of some MSTs, therefore they are consider
 ## Solution
 
 ```kotlin
-import java.util.Arrays
 import java.util.LinkedList
 
 class Solution {
@@ -73,7 +72,7 @@ class Solution {
             mst[i] = LinkedList()
         }
         val mstSet = BooleanArray(edges.size)
-        Arrays.sort(edges) { a: IntArray, b: IntArray ->
+        edges.sortWith { a: IntArray, b: IntArray ->
             Integer.compare(
                 a[2], b[2]
             )