please could you fixed the probleme at the (return result ) line 49 undeclared identifier 'result' thank you and make the program works well ---------------------------------------------#include #include #include // Class to represent an expression class Expression { public: // Constructor to initialize infix or postfix expression based on input direction Expression(std::string input, int direction) { // If direction is 1, store input as infix expression if (direction == 1) infix = input; // If direction is 2, store input as postfix expression else if(direction == 2) postfix = input; } // Method to convert infix expression to postfix std::string inToPost(); // Method to convert postfix expression to infix std::string postToIn(); // Method to evaluate postfix expression and return result double evaluate(); private: std::string infix; std::string postfix; }; // Method to convert infix expression to postfix std::string Expression::inToPost() { // TODO: Add code to convert infix to postfix expression // ... return postfix; } // Method to convert postfix expression to infix std::string Expression::postToIn() { // TODO: Add code to convert postfix to infix expression // ... return infix; } // Method to evaluate postfix expression and return result double Expression::evaluate() { // TODO: Add code to evaluate postfix expression // ... return result; } int main() { // Prompt user to choose the type of expression to enter std::cout << "Enter 1 to enter an expression in infix notation," << std::endl; std::cout << "Enter 2 to enter an expression in postfix notation," << std::endl; int choice; std::cin >> choice; // Get input expression from user std::string input; std::cout << "Enter expression: " << std::endl; std::cin >> input; // Create Expression object with input and direction Expression exp(input, choice); // Prompt user to choose the operation to perform on the expression std::cout << "Enter 1 to convert to postfix notation," << std::endl; std::cout << "Enter 2 to convert to infix notation," << std::endl; std::cout << "Enter 3 to evaluate expression." << std::endl; int operation; std::cin >> operation; // Perform selected operation and display result switch(operation) { case 1: std::cout << "Postfix: " << exp.inToPost() << std::endl; break; case 2: std::cout << "Infix: " << exp.postToIn() << std::endl; break; case 3: std::cout << "Result: " << exp.evaluate() << std::endl; break; default: std::cout << "Invalid choice." << std::endl; break; } return 0; }