Implement exchangePairs and rotateTriples

src/aud/exam/prep/array/FullyUsedArrayProcessor.java

@@ -201,11 +201,6 @@ public class FullyUsedArrayProcessor<T> implements SequenceProcessor<T, FullyUse
         return secondMax;
     }
 
-    @Override
-    public boolean check(FullyUsedArray<T> array) {
-        return true;
-    }
-
     @Override
     public boolean isItemWiseLessOrEqual(FullyUsedArray<T> a, FullyUsedArray<T> b, Comparator<T> cmp) {
         if (b.theArray.length < a.theArray.length) {
@@ -258,12 +253,21 @@ public class FullyUsedArrayProcessor<T> implements SequenceProcessor<T, FullyUse
 
     @Override
     public void exchangePairs(FullyUsedArray<T> array) {
-
+        for (int i = 1; i < array.theArray.length-1; i += 2) {
+            T t = array.theArray[i];
+            array.theArray[i] = array.theArray[i+1];
+            array.theArray[i+1] = t;
+        }
     }
 
     @Override
     public void rotateTriples(FullyUsedArray<T> array) {
-
+        for (int i = 1; i < array.theArray.length-2; i += 3) {
+            T t = array.theArray[i+2];
+            array.theArray[i+2] = array.theArray[i+1];
+            array.theArray[i+1] = array.theArray[i];
+            array.theArray[i] = t;
+        }
     }
 
     @Override
@@ -514,6 +518,11 @@ public class FullyUsedArrayProcessor<T> implements SequenceProcessor<T, FullyUse
         return p;
     }
 
+    @Override
+    public boolean check(FullyUsedArray<T> array) {
+        return true;
+    }
+
     @Override
     public FullyUsedArray<T> create(Iterable<T> iterable) {
         var array = new FullyUsedArray<T>();

test/aud/exam/prep/SequenceProcessorTest.java

@@ -373,6 +373,37 @@ public abstract class SequenceProcessorTest<S> {
         return processor.create(list);
     }
 
+    @ParameterizedTest
+    @ArgumentsSource(ListProvider.class)
+    void testThat_exchangePairsWorks(List<Integer> list) {
+        S s = processor.create(list);
+
+        for (int i = 1; i < list.size()-1; i += 2) {
+            Collections.swap(list, i, i+1);
+        }
+
+        processor.exchangePairs(s);
+
+        assertTrue(processor.check(s));
+        assertIterableEquals(list, processor.iterate(s));
+    }
+
+    @ParameterizedTest
+    @ArgumentsSource(ListProvider.class)
+    void testThat_rotateTriplesWorks(List<Integer> list) {
+        S s = processor.create(list);
+
+        for (int i = 1; i < list.size()-2; i += 3) {
+            Collections.swap(list, i+1, i+2);
+            Collections.swap(list, i, i+1);
+        }
+
+        processor.rotateTriples(s);
+
+        assertTrue(processor.check(s));
+        assertIterableEquals(list, processor.iterate(s));
+    }
+
     @ParameterizedTest
     @ArgumentsSource(ListProvider.class)
     void testThat_doubleAllKeysWorks(List<Integer> list) {