Cleaned up code for some packages (#5094)

* Cleaned up code of some packages

---------

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

src/main/java/com/thealgorithms/greedyalgorithms/ActivitySelection.java

@@ -8,9 +8,9 @@ import java.util.Comparator;
 
 public class ActivitySelection {
     // Function to perform activity selection
-    public static ArrayList<Integer> activitySelection(int startTimes[], int endTimes[]) {
+    public static ArrayList<Integer> activitySelection(int[] startTimes, int[] endTimes) {
         int n = startTimes.length;
-        int activities[][] = new int[n][3];
+        int[][] activities = new int[n][3];
 
         // Create a 2D array to store activities and their start/end times.
         // Each row: [activity index, start time, end time]

src/main/java/com/thealgorithms/greedyalgorithms/CoinChange.java

@@ -10,12 +10,11 @@ public class CoinChange {
     // Function to solve the coin change problem
     public static ArrayList<Integer> coinChangeProblem(int amount) {
         // Define an array of coin denominations in descending order
-        Integer coins[] = {1, 2, 5, 10, 20, 50, 100, 500, 2000};
+        Integer[] coins = {1, 2, 5, 10, 20, 50, 100, 500, 2000};
 
         // Sort the coin denominations in descending order
         Arrays.sort(coins, Comparator.reverseOrder());
 
-        int count = 0; // Variable to keep track of the total number of coins used
         ArrayList<Integer> ans = new ArrayList<>(); // List to store selected coins
 
         // Iterate through the coin denominations
@@ -24,7 +23,6 @@ public class CoinChange {
             if (coins[i] <= amount) {
                 // Repeatedly subtract the coin denomination from the remaining amount
                 while (coins[i] <= amount) {
-                    count++; // Increment the count of coins used
                     ans.add(coins[i]); // Add the coin to the list of selected coins
                     amount -= coins[i]; // Update the remaining amount
                 }

src/main/java/com/thealgorithms/greedyalgorithms/FractionalKnapsack.java

@@ -7,9 +7,9 @@ import java.util.Comparator;
 
 public class FractionalKnapsack {
     // Function to perform fractional knapsack
-    public static int fractionalKnapsack(int weight[], int value[], int capacity) {
+    public static int fractionalKnapsack(int[] weight, int[] value, int capacity) {
         // Create a 2D array to store item indices and their value-to-weight ratios.
-        double ratio[][] = new double[weight.length][2];
+        double[][] ratio = new double[weight.length][2];
 
         // Populate the ratio array with item indices and their value-to-weight ratios.
         for (int i = 0; i < weight.length; i++) {

src/main/java/com/thealgorithms/greedyalgorithms/JobSequencing.java

@@ -31,7 +31,7 @@ public class JobSequencing {
         Boolean[] slots = new Boolean[size];
         Arrays.fill(slots, false);
 
-        int result[] = new int[size];
+        int[] result = new int[size];
 
         // Iterate through jobs to find the optimal job sequence
         for (int i = 0; i < size; i++) {