Update PrintUtil.hpp

Reverse the stack before printing.

codes/cpp/include/PrintUtil.hpp

@@ -210,34 +210,32 @@ class PrintUtil {
         
             printTree(root->left, trunk, false);
         }
+    
         /**
-         * @brief Get the Stack String object
+         * @brief Print a stack
          * 
          * @tparam T 
-         * @param stack 
-         * @return string 
+         * @param stk
          */
         template <typename T>
-        static string getStackString(stack<T> stack) {
-            ostringstream s;
-            if(!stack.empty()){
-                s << stack.top();
-                stack.pop();
+        static void printStack(stack<T> &stk) {
+            // Reverse the input stack
+            stack<T> tmp;
+            while(!stk.empty()) {
+                tmp.push(stk.top());
+                stk.pop();
             }
-            while(!stack.empty()){
-                s << ", " << stack.top();
-                stack.pop();
+            // Generate the string to print
+            ostringstream s;
+            bool flag = true;
+            while(!tmp.empty()) {
+                if (flag) {
+                    s << tmp.top();
+                    flag = false;
+                }
+                else s << ", " << tmp.top();
+                tmp.pop();
             }
-            return "top->" + s.str() + "]";
-        }
-        /**
-         * @brief Print a stack
-         * 
-         * @tparam T 
-         * @param stack
-         */
-        template <typename T>
-        static void printStack(stack<T> &stack) {
-            cout << getStackString(stack) << '\n';
+            cout << "[" + s.str() + "]" << '\n';
         }
 };