KNearestNumbers: use int[] for param and return type for consistency

Author: andrei-punko

Diff for: src/main/java/by/andd3dfx/numeric/KNearestNumbers.java

@@ -1,7 +1,6 @@
 package by.andd3dfx.numeric;
 
 import java.util.ArrayList;
-import java.util.List;
 
 /**
  * Find K nearest numbers for item placed on i-th position in array of numbers.
@@ -24,7 +23,7 @@
  */
 public class KNearestNumbers {
 
-    public static List<Integer> find(int[] nums, int i, int k) {
+    public static int[] find(int[] nums, int i, int k) {
         if (i < 0 || i >= nums.length) {
             throw new IllegalArgumentException("Index `i` is out of array's range!");
         }
@@ -33,7 +32,7 @@ public static List<Integer> find(int[] nums, int i, int k) {
         }
 
         if (k == 0) {
-            return List.of();
+            return new int[]{};
         }
         var result = new ArrayList<Integer>();
         result.add(nums[i]);
@@ -52,7 +51,9 @@ public static List<Integer> find(int[] nums, int i, int k) {
                 right++;
             }
         }
-        return result;
+        return result.stream()
+                .mapToInt(value -> value)
+                .toArray();
     }
 
     private static int determineLeftDistance(int[] nums, int left, int curr) {

Diff for: src/test/java/by/andd3dfx/numeric/KNearestNumbersTest.java

@@ -1,9 +1,8 @@
 package by.andd3dfx.numeric;
 
-import org.apache.commons.collections4.CollectionUtils;
 import org.junit.Test;
 
-import java.util.List;
+import java.util.Arrays;
 
 import static by.andd3dfx.numeric.KNearestNumbers.find;
 import static org.assertj.core.api.Assertions.assertThat;
@@ -21,8 +20,8 @@ public void testFind() {
 
         var result = find(new int[]{1, 2, 3, 4, 5, 6}, 3, 2);
         assertTrue(
-                CollectionUtils.isEqualCollection(result, List.of(4, 3)) ||
-                        CollectionUtils.isEqualCollection(result, List.of(4, 5))
+                Arrays.equals(result, new int[]{4, 3}) ||
+                        Arrays.equals(result, new int[]{4, 5})
         );
 
         assertThat(find(new int[]{1, 2, 3, 4, 5, 6}, 0, 3))