4. Complete the code inside the box class dtype int id; float rate; int hours; public: dtype(); dtype(); void insert_val(ifstream &); void print_val(ofstream &); class op dtype s[12]; public: op(); pop(); ??? read_into_array(????); // reads from a file into the array of objects ??? printoffile(????);// Outputs from the array to a file // Write a COMPLETE Code for "print_val" method along with the function heading // Write a COMPLETE code for "printtofile" method along with the function heading. // Write a COMPLETE code for "main" to call the above method/s