added files

lesson3Collections.java

@@ -0,0 +1,11 @@
+package ru.geekbrains;
+
+import java.util.Arrays;
+
+public class lesson3Collections {
+    public static void main(String[] args) {
+        int[] array = new int[] {350, 2, 45, 45, 6, 90, 5, 10, 1, 11};
+        sortCollections.quickSorting(array, 0, array.length - 1);
+        System.out.println(Arrays.toString(array));
+    }
+}

sortCollections.java

@@ -0,0 +1,43 @@
+package ru.geekbrains;
+
+public class sortCollections {
+    public static void quickSorting(int[] arr, int from, int to) {
+        if (from < to) {
+            int divideIndex = partition(arr, from, to);
+            quickSorting(arr, from, divideIndex - 1);
+            quickSorting(arr, divideIndex, to);
+        }
+    }
+
+        public static int partition(int[] arr, int from, int to) { // от 0 до 9
+        int rightIndex = to;
+        int leftIndex = from;
+
+        int pivot = arr[from];
+        while (leftIndex <= rightIndex) {
+
+            while (arr[leftIndex] < pivot) {
+                leftIndex ++;
+            }
+
+            while (arr[rightIndex] > pivot) {
+                rightIndex --;
+            }
+
+            if (leftIndex <= rightIndex) {
+                swap(arr, rightIndex, leftIndex);
+                leftIndex ++;
+                rightIndex --;
+            }
+        }
+        return leftIndex;
+
+}
+
+
+    public static void swap(int[] array, int index1, int index2) {
+        int tmp = array[index1];
+        array[index1] = array[index2];
+        array[index2] = tmp;
+    }
+}