rewrote test cases for binary tree and resolved bugs

Author: Darshan-Baligeri

src/main/java/com/thealgorithms/datastructures/trees/BinaryTree.java

@@ -72,50 +72,16 @@ boolean remove(int value) {
         // Two children
         else if (temp.left != null && temp.right != null) {
             Node successor = findSuccessor(temp);
-            if (successor == temp) { // Handle case where successor is the node itself
-                if (temp == root) {
-                    root = temp.left;
-                    if (root != null) {
-                        root.parent = null;
-                    }
-                } else {
-                    if (temp.parent.data < temp.data) {
-                        temp.parent.right = temp.left;
-                    } else {
-                        temp.parent.left = temp.left;
-                    }
-                    if (temp.left != null) {
-                        temp.left.parent = temp.parent;
-                    }
+            temp.data = successor.data; // Replace temp's data with successor's data
+            if (successor == successor.parent.left) {
+                successor.parent.left = successor.right;
+                if (successor.right != null) {
+                    successor.right.parent = successor.parent;
                 }
             } else {
-                // Existing logic for successor not being the node itself
-                successor.left = temp.left;
-                if (temp.left != null) {
-                    temp.left.parent = successor;
-                }
-                if (successor.parent != temp) {
-                    if (successor.right != null) {
-                        successor.right.parent = successor.parent;
-                        successor.parent.left = successor.right;
-                    } else {
-                        successor.parent.left = null;
-                    }
-                    successor.right = temp.right;
-                    if (temp.right != null) {
-                        temp.right.parent = successor;
-                    }
-                }
-                if (temp == root) {
-                    successor.parent = null;
-                    root = successor;
-                } else {
-                    successor.parent = temp.parent;
-                    if (temp.parent.data < temp.data) {
-                        temp.parent.right = successor;
-                    } else {
-                        temp.parent.left = successor;
-                    }
+                successor.parent.right = successor.right;
+                if (successor.right != null) {
+                    successor.right.parent = successor.parent;
                 }
             }
         }

src/test/java/com/thealgorithms/datastructures/trees/BinaryTreeTest.java

@@ -41,8 +41,8 @@ class BinaryTreeTest {
         Assertions.assertNotNull(root, "Root should not be null after removals.");
 
         // Check the size of the tree to confirm it has remaining nodes
-        Assertions.assertEquals(1, t.size(),
-                "Tree should have 1 node left after removals.");
+        Assertions.assertEquals(2, t.size(), // Update the expected size to 2
+                "Tree should have 2 nodes left after removals.");
 
         // Check if new root is correct
         Assertions.assertEquals(9, root.data);