C++ warning and error function

#include <iostream>
#include <conio.h>
#include <string>
#include <iomanip>

using namespace std;
 
class payroll {
 
    private:
 
    string name;
    int days_work;
    float rate;
    float pay;
    float sss;
    float phil;
    float deduct;
    float totalpay;
    
    public :
 
      int get_info();
      void display_info();
};
 
////////////////////////////////////////////////////////////////////
const int PASSLEN = 4;
 
string passget();
 

void start()
	{
 
	string password;
	cout << "\n\n";
	cout << "\t SECURITY FORM";
	cout << "\n\n";
	cout << "Enter Your Password: ";
	password = passget();
 
	if (password == "bscs") {
	    cout << "\n\n";
	    cout << "Password Accepted";
	    cout << "\n\n\n";
        
        payroll emp;
        emp.get_info();
        emp.display_info();
	}
	else {
	    cout << "\n\n";
	    cout << "Password Denied Try Again !!!";
	    start();
	}
	}  // End of Start Function

 
int main()
{
    start();
	getch();
}
 
string passget()
{
	char password[PASSLEN], letter;
	int loop;
	int len;
	string password2;
 
		//Get Password and replace letters with *--------------
		loop = 0;
		while(loop != PASSLEN)
		{
			password[loop] = '\0';
			loop++;
		}
		loop = 0;
		len = 0;
		letter = '\0';
		while( letter != '\r' )
		{
			letter = getch();
			if( letter == '\b' && password[0] == '\0')
			{
				loop = 0;
				len = 0;
			}
			else
			{
				if( letter == '\b' && password[0] != '\0')
				{
					cout << "\b";
					cout << " ";
					cout << "\b";
					loop--;
					password[loop] = '\0';
					len--;
				}
				else
				{
					if( isprint( letter ) != 0 && loop < PASSLEN)
					{
						password[loop] = tolower(letter);
						cout << "*" ;
					}
					loop++;
					if (loop <= PASSLEN)
						len++;
				}
			}
		}
 
		//Convert Password from character array to string
		loop = 0;
		len = len;
		password2 = "";
		while (loop != len)
		{
		password2 = password2+password[loop];
		loop++;
		}
 
	return password2;
 } // End of Function Password

/////////////////////////////////////////////////////////////////////
int payroll :: get_info()
 {
     cout << "\t\t Welcome to Payroll System";
     cout << "\n\n";
     cout << "Enter Employees Name     : ";
     getline(cin,name);
     cout << "Enter No. of Days Worked : ";
     cin >> days_work;
     cout << "Enter Daily Rate         : ";
     cin >> rate;
     cout << "Enter SSS or GSIS        : ";
     cin >> sss;
     cout << "Enter Philhealth         : ";
     cin >> phil;
     
     cout << fixed << setprecision(4);
     pay = (days_work * rate);
     deduct = (sss + phil);
     totalpay= (pay - deduct);
 }
 
 void payroll ::display_info()
    {
 
     cout << "\n\n";
     cout << "*****@@---DETAILED REPORT---@@*****";
     cout << "\n\n";
     cout << "\nEmployees Name     : " << name;
     cout << "\n\n";
     cout << "\nEmployees Salay is : $" << pay;
     cout << "\n\n";
     cout << "\nEmployees SSS deduction is : $" << sss;
     cout << "\n\n";
     cout << "\nEmployees Philhealt deduction is : $" << phil;
     cout << "\n\n";
     cout << "\nEmployees Total deduction is : $" << deduct;
     cout << "\n\n";
     cout << "\n\n";
     cout << "\n\n";
     cout << "\nEmployees Total Salary is : $" << totalpay;
     cout << "\n\n";
     system("pause");
    }
////////////////////////////////////////////////