added quicksort in java

quicksort.java

@@ -0,0 +1,58 @@
+public class QuickSort {
+
+    // Function to perform QuickSort
+    public static void quickSort(int[] arr, int low, int high) {
+        if (low < high) {
+            // Partition the array and get pivot index
+            int pi = partition(arr, low, high);
+
+            // Recursively sort elements before and after partition
+            quickSort(arr, low, pi - 1);
+            quickSort(arr, pi + 1, high);
+        }
+    }
+
+    // Partition function
+    private static int partition(int[] arr, int low, int high) {
+        int pivot = arr[high]; // choosing the last element as pivot
+        int i = low - 1;       // index of smaller element
+
+        for (int j = low; j < high; j++) {
+            // if current element <= pivot, swap
+            if (arr[j] <= pivot) {
+                i++;
+                // swap arr[i] and arr[j]
+                int temp = arr[i];
+                arr[i] = arr[j];
+                arr[j] = temp;
+            }
+        }
+
+        // swap pivot into the correct position
+        int temp = arr[i + 1];
+        arr[i + 1] = arr[high];
+        arr[high] = temp;
+
+        return i + 1; // return pivot index
+    }
+
+    // Utility function to print the array
+    public static void printArray(int[] arr) {
+        for (int num : arr) {
+            System.out.print(num + " ");
+        }
+        System.out.println();
+    }
+
+    // Main method
+    public static void main(String[] args) {
+        int[] arr = {10, 7, 8, 9, 1, 5};
+        System.out.println("Original Array:");
+        printArray(arr);
+
+        quickSort(arr, 0, arr.length - 1);
+
+        System.out.println("Sorted Array:");
+        printArray(arr);
+    }
+}