Welcome! Today, we are going to explore an engaging task that involves managing employee records within a company. Specifically, we will work with nested std::map and std::vector to add projects and tasks for employees and retrieve those tasks as needed. This exercise will help you understand how to manipulate nested data structures efficiently in C++.

Let's start by discussing the methods we will implement in our EmployeeRecords class.

• bool add_project(const std::string& employee_id, const std::string& project_name) - this method adds a new project to an employee's list of projects. If the project already exists for that employee, the method returns false. Otherwise, it adds the project and returns true.
• bool add_task(const std::string& employee_id, const std::string& project_name, const std::string& task) - this method adds a new task to a specified project for an employee. If the project does not exist for that employee, the method returns false. If the task is added successfully, it returns true.
• std::vector<std::string> get_tasks(const std::string& employee_id, const std::string& project_name) - this method retrieves all tasks for a specified project of an employee. If the project does not exist for that employee, the method returns an empty vector. Otherwise, it returns the list of tasks.