style: enable HideUtilityClassConstructor in checkstyle (#5147)

src/main/java/com/thealgorithms/datastructures/graphs/A_Star.java

@@ -9,7 +9,9 @@ import java.util.Comparator;
 import java.util.List;
 import java.util.PriorityQueue;
 
-public class A_Star {
+public final class A_Star {
+    private A_Star() {
+    }
 
     private static class Graph {
 

src/main/java/com/thealgorithms/datastructures/graphs/BipartiteGrapfDFS.java

@@ -14,7 +14,9 @@ import java.util.Arrays;
  *
  * Output : YES
  */
-public class BipartiteGrapfDFS {
+public final class BipartiteGrapfDFS {
+    private BipartiteGrapfDFS() {
+    }
 
     private static boolean bipartite(int V, ArrayList<ArrayList<Integer>> adj, int[] color, int node) {
         if (color[node] == -1) {

src/main/java/com/thealgorithms/datastructures/graphs/ConnectedComponent.java

@@ -107,7 +107,9 @@ class Graph<E extends Comparable<E>> {
     }
 }
 
-public class ConnectedComponent {
+public final class ConnectedComponent {
+    private ConnectedComponent() {
+    }
 
     public static void main(String[] args) {
         Graph<Character> graphChars = new Graph<>();

src/main/java/com/thealgorithms/datastructures/graphs/Cycles.java

@@ -78,7 +78,9 @@ class Cycle {
     }
 }
 
-public class Cycles {
+public final class Cycles {
+    private Cycles() {
+    }
 
     public static void main(String[] args) {
         Cycle c = new Cycle();

src/main/java/com/thealgorithms/datastructures/graphs/Graphs.java

@@ -120,7 +120,9 @@ class AdjacencyListGraph<E extends Comparable<E>> {
     }
 }
 
-public class Graphs {
+public final class Graphs {
+    private Graphs() {
+    }
 
     public static void main(String[] args) {
         AdjacencyListGraph<Integer> graph = new AdjacencyListGraph<>();

src/main/java/com/thealgorithms/datastructures/graphs/KahnsAlgorithm.java

@@ -130,7 +130,9 @@ class TopologicalSort<E extends Comparable<E>> {
 /**
  * A driver class that sorts a given graph in topological order.
  */
-public class KahnsAlgorithm {
+public final class KahnsAlgorithm {
+    private KahnsAlgorithm() {
+    }
 
     public static void main(String[] args) {
         // Graph definition and initialization

src/main/java/com/thealgorithms/datastructures/graphs/MatrixGraphs.java

@@ -12,7 +12,9 @@ import java.util.Queue;
  *
  * @author Unknown
  */
-public class MatrixGraphs {
+public final class MatrixGraphs {
+    private MatrixGraphs() {
+    }
 
     public static void main(String[] args) {
         AdjacencyMatrixGraph graph = new AdjacencyMatrixGraph(10);