sortArrayIntoEvensThenOdds

arraz/src/main/java/Arraz.java

@@ -186,7 +186,7 @@ public class Arraz {
     }
 
     public ArrayList<Integer> makeMeAnArrayListFromArray(int[] intsArr){
-        ArrayList<Integer> retArr = new ArrayList<Integer>();
+        ArrayList<Integer> retArr = new ArrayList<>();
         for (int i: intsArr) {
             retArr.add(i);
         }
@@ -237,7 +237,10 @@ public class Arraz {
                 arrayList.add(i);
             }
         }
-        sum = arrayList.stream().mapToDouble(Integer::doubleValue).sum();
+        sum = arrayList.stream()
+                .mapToDouble(Integer::doubleValue)
+                .sum();
+
         return sum / arrayList.size();
     }
 
@@ -312,4 +315,61 @@ public class Arraz {
         }
         return retArr;
     }
+
+    public int[] removeFirstItemAndCopy(int[] arr) {
+        int[] retArr = new int[arr.length - 1];
+
+        for (int i = 1; i < arr.length; i++) {
+            retArr[i-1] = arr[i];
+        }
+        return retArr;
+    }
+
+    public int[] insertAtStartAndCopy(int[] arr, int insert) {
+        int[] retArr = new int[arr.length + 1];
+        retArr[0] = insert;
+
+        for (int i = 0; i < arr.length; i++) {
+            retArr[i+1] = arr[i];
+        }
+        return retArr;
+    }
+
+    public int[] insertAtEndAndCopy(int[] arr, int insert) {
+        int[] retArr = new int[arr.length + 1];
+        retArr[retArr.length - 1] = insert;
+
+        for (int i = 0; i < arr.length; i++) {
+            retArr[i] = arr[i];
+        }
+        return retArr;
+    }
+
+    public int[] sortArrayIntoEvensThenOdds(int[] arr) {
+        ArrayList<Integer> even = new ArrayList<>();
+        ArrayList<Integer> odd = new ArrayList<>();
+        int[] retArr = new int[arr.length];
+
+        for (int i: arr) {
+            if (i % 2 == 0){
+                even.add(i);
+            }
+            else {
+                odd.add(i);
+            }
+        }
+
+        int index = 0;
+        for (int i: even) {
+            retArr[index] = i;
+            index++;
+        }
+
+        for (int i: odd) {
+            retArr[index] = i;
+            index++;
+        }
+
+        return retArr;
+    }
 }

arraz/src/test/java/ArrazTest.java

@@ -668,4 +668,104 @@ public class ArrazTest {
         //THEN
         Assert.assertEquals(arr[2], actual[actual.length - 1]);
     }
+
+    @Test
+    public void test1removeFirstItemAndCopy(){
+        //GIVEN
+        int[] arr = {1, 2, 3, 4, 5};
+        //WHEN
+        int[] retArr = arraz.removeFirstItemAndCopy(arr);
+        int expected = 4;
+        int actual = retArr.length;
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void test2removeFirstItemAndCopy(){
+        //GIVEN
+        int[] arr = {1, 2, 3, 4, 5};
+        //WHEN
+        int[] retArr = arraz.removeFirstItemAndCopy(arr);
+        int expected = 2;
+        int actual = retArr[0];
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void test1insertAtStartAndCopy(){
+        //GIVEN
+        int[] arr = {1, 2, 3, 4, 5};
+        int insert = 777;
+        //WHEN
+        int[] retArr = arraz.insertAtStartAndCopy(arr, insert);
+        int expected = 6;
+        int actual = retArr.length;
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void test2insertAtStartAndCopy(){
+        //GIVEN
+        int[] arr = {1, 2, 3, 4, 5};
+        int insert = 777;
+        //WHEN
+        int[] retArr = arraz.insertAtStartAndCopy(arr, insert);
+        int expected = 777;
+        int actual = retArr[0];
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void test1insertAtEndAndCopy(){
+        //GIVEN
+        int[] arr = {1, 2, 3, 4, 5};
+        int insert = 777;
+        //WHEN
+        int[] retArr = arraz.insertAtEndAndCopy(arr, insert);
+        int expected = 777;
+        int actual = retArr[retArr.length - 1];
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void test2insertAtEndAndCopy(){
+        //GIVEN
+        int[] arr = {1, 2, 3, 4, 5};
+        int insert = 777;
+        //WHEN
+        int[] retArr = arraz.insertAtEndAndCopy(arr, insert);
+        int expected = 6;
+        int actual = retArr.length;
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+    // sortArrayIntoEvensThenOdds
+    @Test
+    public void test1sortArrayIntoEvensThenOdds(){
+        //GIVEN
+        int[] arr = {4,5,102,6,-7,12,-32,92,8};
+        //WHEN
+        int[] retArr = arraz.sortArrayIntoEvensThenOdds(arr);
+        int expected = 4;
+        int actual = retArr[0];
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void test2sortArrayIntoEvensThenOdds(){
+        //GIVEN
+        int[] arr = {4,5,102,6,-7,12,-32,92,8};
+        //WHEN
+        int[] retArr = arraz.sortArrayIntoEvensThenOdds(arr);
+        int expected = -7;
+        int actual = retArr[retArr.length - 1];
+        //THEN
+        Assert.assertEquals(expected, actual);
+    }
 }