BAEL-3400 (#8113)

* BAEL-3400 * BALE-3400 | moved to algorithm-miscellaneous-5 * BAEL-3400 | added modifiers
2019-11-05 02:40:19 +01:00
parent cdeb947e42
commit f2d9829b91
5 changed files with 162 additions and 0 deletions
@@ -0,0 +1,26 @@
+package com.baeldung.algorithms.balancedbinarytree;
+
+import org.junit.Test;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertFalse;
+
+public class BalancedBinaryTreeUnitTest extends BinaryTreeDataProvider {
+
+    @Test
+    public void givenBalancedTrees_whenCallingIsBalanced_ShouldReturnTrue() {
+        for (Tree tree : balancedTrees()) {
+            assertTrue(toString(tree) + " should be balanced", BalancedBinaryTree.isBalanced(tree));
+        }
+    }
+
+    @Test
+    public void givenUnbalancedTrees_whenCallingIsBalanced_ShouldReturnFalse() {
+        for (Tree tree : unbalancedTrees()) {
+            assertFalse(toString(tree) + " should not be balanced", BalancedBinaryTree.isBalanced(tree));
+        }
+    }
+
+    private String toString(Tree tree) {
+        return tree != null ? tree.toString() : "null";
+    }
+}
@@ -0,0 +1,69 @@
+package com.baeldung.algorithms.balancedbinarytree;
+
+import java.util.Arrays;
+import java.util.Collection;
+
+class BinaryTreeDataProvider {
+
+    static Collection<Tree> balancedTrees() {
+        return Arrays.asList(
+            null,
+            leaf(1),
+            tree(1, leaf(2), leaf(3)),
+            tree(
+                1,
+                leaf(2),
+                tree(3, leaf(4), null)
+            ),
+            tree(
+                1,
+                tree(
+                    2,
+                    tree(3, leaf(4), null),
+                    leaf(5)
+                ),
+                tree(
+                    6,
+                    leaf(7),
+                    tree(8, null, leaf(9))
+                )
+            )
+        );
+    }
+
+    static Collection<Tree> unbalancedTrees() {
+        return Arrays.asList(
+            tree(
+                1,
+                tree(2, leaf(3), null),
+                null
+            ),
+            tree(
+                1,
+                tree(
+                    2,
+                    tree(3, leaf(4), leaf(5)),
+                    null
+                ),
+                tree(6, leaf(7), null)
+            ),
+            tree(
+                1,
+                tree(2, leaf(3), null),
+                tree(
+                    4,
+                    tree(5, leaf(6), leaf(7)),
+                    null
+                )
+            )
+        );
+    }
+
+    private static Tree leaf(int value) {
+        return new Tree(value, null, null);
+    }
+
+    private static Tree tree(int value, Tree left, Tree right) {
+        return new Tree(value, left, right);
+    }
+}