making code more clean and readable

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

@@ -8,7 +8,7 @@ public class FibonacciHeap {
     private static int totalCuts = 0;
     private int numOfTrees = 0;
     private int numOfHeapNodes = 0;
-    private int markedHeapNoodesCounter = 0;
+    private int markedHeapNodesCounter = 0;
 
     /*
      * a constructor for an empty Heap
@@ -190,7 +190,7 @@ private void decreaseKey(HeapNode x, int delta) {
      * Potential = #trees + 2*#markedNodes
      */
     public int potential() {
-        return numOfTrees + (2 * markedHeapNoodesCounter);
+        return numOfTrees + (2 * markedHeapNodesCounter);
     }
 
     /**
@@ -232,7 +232,7 @@ private void cascadingCuts(HeapNode curr) {
         if (!curr.isMarked()) { // stop the recursion
             curr.mark();
             if (!curr.isRoot()) {
-                this.markedHeapNoodesCounter++;
+                this.markedHeapNodesCounter++;
             }
         } else {
             if (curr.isRoot()) {
@@ -252,7 +252,7 @@ private void cascadingCuts(HeapNode curr) {
     private void cut(HeapNode curr) {
         curr.parent.rank--;
         if (curr.marked) {
-            this.markedHeapNoodesCounter--;
+            this.markedHeapNodesCounter--;
             curr.marked = false;
         }
         if (curr.parent.child == curr) { // we should change the parent's child

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

@@ -22,7 +22,7 @@ public MaxHeap(List<HeapElement> listElements) {
                 System.out.println("Null element. Not added to heap");
             }
         }
-        if (maxHeap.size() == 0) {
+        if (maxHeap.isEmpty()) {
             System.out.println("No element has been added, empty heap.");
         }
     }

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

@@ -22,7 +22,7 @@ public MinHeap(List<HeapElement> listElements) {
                 System.out.println("Null element. Not added to heap");
             }
         }
-        if (minHeap.size() == 0) {
+        if (minHeap.isEmpty()) {
             System.out.println("No element has been added, empty heap.");
         }
     }

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

@@ -14,11 +14,11 @@
  */
 public class MinPriorityQueue {
 
-    private int[] heap;
-    private int capacity;
+    private final int[] heap;
+    private final int capacity;
     private int size;
 
-    // calss the constructor and initializes the capacity
+    // class the constructor and initializes the capacity
     MinPriorityQueue(int c) {
         this.capacity = c;
         this.size = 0;