style: enabled InnerAssignment in checkstyle (#5162)

* style: enabled InnerAssignment in checkstyle

* Refactor code formatting in KnapsackMemoization.java and UnionFind.java

* style: remove redundant blank line

* style: mark `includeCurrentItem` and `excludeCurrentItem` as `final`

* style: remove `KnapsackMemoization` from `pmd-exclude.properties`

* style: use `final`

---------

Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com>

src/main/java/com/thealgorithms/datastructures/dynamicarray/DynamicArray.java

@@ -121,7 +121,8 @@ public class DynamicArray<E> implements Iterable<E> {
             System.arraycopy(elements, index + 1, elements, index, newSize - index);
         }
 
-        elements[this.size = newSize] = null;
+        this.size = newSize;
+        this.elements[this.size] = null;
     }
 
     private E getElement(final int index) {

src/main/java/com/thealgorithms/datastructures/heaps/LeftistHeap.java

@@ -20,7 +20,8 @@ public class LeftistHeap {
         // Node constructor setting the data element and left/right pointers to null
         private Node(int element) {
             this.element = element;
-            left = right = null;
+            left = null;
+            right = null;
             npl = 0;
         }
     }

src/main/java/com/thealgorithms/datastructures/queues/CircularQueue.java

@@ -54,7 +54,8 @@ public class CircularQueue {
             int res = arr[beginningOfQueue];
             arr[beginningOfQueue] = Integer.MIN_VALUE;
             if (beginningOfQueue == topOfQueue) {
-                beginningOfQueue = topOfQueue = -1;
+                beginningOfQueue = -1;
+                topOfQueue = -1;
             } else if (beginningOfQueue + 1 == size) {
                 beginningOfQueue = 0;
             } else {

src/main/java/com/thealgorithms/datastructures/queues/LinkedQueue.java

@@ -44,7 +44,9 @@ public class LinkedQueue<T> implements Iterable<T> {
      * Init LinkedQueue
      */
     public LinkedQueue() {
-        front = rear = new Node<>();
+
+        front = new Node<>();
+        rear = front;
     }
 
     /**
@@ -146,7 +148,8 @@ public class LinkedQueue<T> implements Iterable<T> {
 
             @Override
             public T next() {
-                return (node = node.next).data;
+                node = node.next;
+                return node.data;
             }
         };
     }

src/main/java/com/thealgorithms/datastructures/trees/PrintTopViewofTree.java

@@ -15,7 +15,8 @@ class TreeNode {
     // Constructor
     TreeNode(int key) {
         this.key = key;
-        left = right = null;
+        left = null;
+        right = null;
     }
 }
 

src/main/java/com/thealgorithms/datastructures/trees/RedBlackBST.java

@@ -201,7 +201,8 @@ public class RedBlackBST {
     }
 
     boolean delete(Node z) {
-        if ((z = findNode(z, root)) == null) {
+        Node result = findNode(z, root);
+        if (result == null) {
             return false;
         }
         Node x;