test: add some more

src/main/java/WardrobeBuilder/WardrobeBuilder.java

@@ -1,12 +1,47 @@
 package WardrobeBuilder;
 
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
 public class WardrobeBuilder {
-    public static List<List<Integer>> allCombinations(Set<Integer> elememts, int target) {
-        List<Integer> wardrobe = List.of(50);
-        return List.of(wardrobe);
+    Set<Integer> elements;
+    int target;
+
+    public WardrobeBuilder(Set<Integer> elements, int target){
+        this.elements = elements;
+        this.target = target;
+    }
+
+    public Set<List<Integer>> allCombinations() {
+        Set<List<Integer>> combinations = completeCombination(new ArrayList<>());
+        Set<List<Integer>> newCombinations;
+        for (Integer element : elements) {
+            newCombinations = new HashSet<>();
+            for (List<Integer> combination : combinations) {
+                newCombinations.addAll(completeCombination(combination));
+            }
+            combinations = newCombinations;
+        }
+        return combinations;
+    }
+
+    private Set<List<Integer>> completeCombination(List<Integer> combination) {
+        Integer currentSum = combination.stream().reduce(0, Integer::sum);
+        if (currentSum == target) {
+            return Set.of(combination);
+        }
+
+        Set<List<Integer>> combinations = new HashSet<>();
+        for (Integer element : elements) {
+            if (currentSum + element <= target) {
+                List<Integer> newCombination = new ArrayList<>(combination);
+                newCombination.add(element);
+                newCombination.sort(Integer::compareTo);
+                combinations.add(newCombination);
+            }
+        }
+        return combinations;
     }
 }

src/test/java/MainTest.java

@@ -10,17 +10,52 @@ class MainTest {
     @org.junit.jupiter.api.Test
     void onlyOneWardrobeFromOneElement() {
         Set<Integer> elememts = Set.of(50);
-        List<List<Integer>> wardrobes = WardrobeBuilder.allCombinations(elememts, 50);
+        WardrobeBuilder wardrobeBuilder = new WardrobeBuilder(elememts, 50);
+        Set<List<Integer>> wardrobes = wardrobeBuilder.allCombinations();
         assertEquals(1, wardrobes.size());
     }
 
     @org.junit.jupiter.api.Test
-    void sameHeightFromOneElement() {
-        Set<Integer> elememts = Set.of(50);
-        List<List<Integer>> wardrobes = WardrobeBuilder.allCombinations(elememts, 50);
-        List<Integer> wardrobe = wardrobes.getFirst();
+    void targetHeightFromOneElement() {
+        Integer target = 75;
+        Set<Integer> elememts = Set.of(target);
+        WardrobeBuilder wardrobeBuilder = new WardrobeBuilder(elememts, target);
+        Set<List<Integer>> wardrobes = wardrobeBuilder.allCombinations();
+        List<Integer> wardrobe = wardrobes.iterator().next();
+        Integer sum = wardrobe.stream().reduce(0, Integer::sum);
+        assertEquals(target, sum);
+    }
+
+    @org.junit.jupiter.api.Test
+    void targetHeightSumFromTwoElements() {
+        Set<Integer> elememts = Set.of(50, 75);
+        Integer target = 125;
+        WardrobeBuilder wardrobeBuilder = new WardrobeBuilder(elememts, target);
+
+        Set<List<Integer>> wardrobes = wardrobeBuilder.allCombinations();
+        List<Integer> wardrobe = wardrobes.iterator().next();
+        assertEquals(2, wardrobe.size());
+    }
+
+    @org.junit.jupiter.api.Test
+    void noDuplicatesForTwoElements() {
+        Set<Integer> elememts = Set.of(50, 75);
+        Integer target = 125;
+        WardrobeBuilder wardrobeBuilder = new WardrobeBuilder(elememts, target);
+
+        Set<List<Integer>> wardrobes = wardrobeBuilder.allCombinations();
         assertEquals(1, wardrobes.size());
-        Integer elememt = wardrobe.getFirst();
-        assertEquals(50, elememt);
+    }
+
+    @org.junit.jupiter.api.Test
+    void targetHeightPartialFromTwoElements() {
+        Set<Integer> elememts = Set.of(50, 75);
+        Integer target = 50;
+        WardrobeBuilder wardrobeBuilder = new WardrobeBuilder(elememts, target);
+
+        Set<List<Integer>> wardrobes = wardrobeBuilder.allCombinations();
+        List<Integer> wardrobe = wardrobes.iterator().next();
+        Integer sum = wardrobe.stream().reduce(0, Integer::sum);
+        assertEquals(target, sum);
     }
 }