Looked up how to do iterative traversal with a stack

BST.java

@@ -65,17 +65,18 @@ public class BST {
     public String inOrder() {
         // TODO: implement this method using a non-recursive solution
         String return_string = "";
-        BSTNode[] stack = new BSTNode[size()];
-        int stack_pointer = 0;
+        Stack<BSTNode> stack = new Stack<BSTNode>();
         BSTNode current = m_root;
-        while (true) {
-            while (current.getLeft() != null) {
-                stack[stack_pointer] = current;
-                stack_pointer++;
+        while ((current != null) || (stack.size() > 0)) {
+            while (current != null) {
+                stack.push(current);
                 current = current.getLeft();
             }
+            current = stack.pop();
+            return_string += current.getInfo() + " ";
+            current = current.getRight();
         }
-        return return_string; // replace this statement with your own return
+        return return_string;
     }
 
     // This method returns the smallest element in the binary search tree. You