cohort 42.1 hw #18, lesson #19

Author: biblelamp

BerlinAIT/Cohort42.1/src/lesson18/homework/HomeWork18.java

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+package lesson18.homework;
+
+/**
+ * AIT-TR, cohort 42.1, Java Basic, hw #18
+ *
+ * @author Sergey Iryupin
+ * @version 26-Feb-24
+ */
+public class HomeWork18 {
+    public static void main(String[] args) {
+        // task #1
+        Simple s1 = new Simple();
+        System.out.println(Simple.getCount());
+        Simple s2 = new Simple();
+        System.out.println(Simple.getCount());
+    }
+}

BerlinAIT/Cohort42.1/src/lesson18/homework/Simple.java

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+package lesson18.homework;
+
+public class Simple {
+    private static int count;
+
+    public Simple() {
+        count++;
+    }
+
+    public static int getCount() {
+        return count;
+    }
+}

BerlinAIT/Cohort42.1/src/lesson19/Lesson19.java

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+package lesson19;
+
+import java.util.ArrayList;
+
+/**
+ * AIT-TR, cohort 42.1, Java Basic, Lesson #19
+ *
+ * @version 26-Feb-24
+ */
+public class Lesson19 {
+    public static void main(String[] args) {
+        RubberArray ra = new RubberArray();
+        ra.add(8);
+        ra.add(12);
+        ra.add(-1);
+        ra.add(3);
+        ra.add(25);
+        System.out.println(ra);
+        System.out.println(ra.get(2));
+        ra.remove(2);
+        System.out.println(ra);
+    }
+}

BerlinAIT/Cohort42.1/src/lesson19/RubberArray.java

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+package lesson19;
+
+public class RubberArray {
+
+    private final int INIT_DATA_SIZE = 10;
+    private final float RESIZE_KOEF = 1.5f;
+    private int[] data;
+    private int length;
+
+    public RubberArray() {
+        data = new int[INIT_DATA_SIZE];
+        length = 0;
+    }
+
+    public int get(int idx) {
+        return data[idx];
+    }
+
+    public void add(int value) {
+        if (length == data.length) {
+            // create new array, length *= 1.5
+            int[] newData = new int[(int) (data.length * RESIZE_KOEF)];
+            // move all items to new array
+            for (int i = 0; i < data.length; i++) {
+                newData[i] = data[i];
+            }
+            // change link to new array
+            data = newData;
+        }
+        // add value
+        data[length] = value;
+        length++;
+    }
+
+    public void add(int value, int idx) {
+        // TODO implement
+    }
+
+    public void remove(int idx) {
+        // move elements right to left from idx
+        for (int i = idx; i < data.length - 1; i++) {
+            data[i] = data[i + 1];
+        }
+        length--;
+    }
+
+    @Override
+    public String toString() {
+        // TODO use StringBuilder instead of String
+        String str = "[";
+        for (int i = 0; i < length; i++) {
+            str += String.valueOf(data[i]);
+            if (i < length - 1) {
+                str += ", ";
+            }
+        }
+        return str + "]";
+    }
+}