How can I access elements of a vecotor in C++ - c++

Question

Actually, I am rookie, and I started to learning this language a few months age. Now, I confronted with an insoluble issue. I devised a program to get information of numerous employee's specification and store it in a vector. In order to acquire better performance, I designed a class named "Employee", and defined a function to give some options to user, like adding new employee, promotion a specific employee's salary and so on.
I defined my matching criterion through operators, but there is an error in program, and that is when I want to display, the output is completely weird. it looks like a some kind of Chinese letter :-)
here is my code:
Thanks
My major problem is when it comes displaying employee's specification
#include <iostream>
#include <string>
#include <vector>
#include <memory>
#include <sstream>
using namespace std;
class Employee
{
public:
Employee(string FirstName, string LastName, int age , double Salary, bool Status ) ://constructor
fName(FirstName), lName(LastName), EmpAge(age), EmpSalary(Salary), RecruitmentStatus(Status) {};
void setSalary(const double&);
void SetRecruitmentStatus(const bool&);
void Promote(const double&);
//====================================//
operator const char* ()
{
ostringstream formattedOutput;
formattedOutput << this->fName.c_str() << " " << (this->lName.c_str()) << " | " << this->EmpAge << " | " << this->EmpSalary << ((RecruitmentStatus) ? "Working" : "Fired");
string output = formattedOutput.str();
return output.c_str();
}
bool operator == (const Employee& anotherEmployee)const
{
return (this->lName == anotherEmployee.lName);
}
bool operator < (const Employee& anotherEmployee)const
{
return (this->EmpSalary < anotherEmployee.EmpSalary);
}
private:
string fName, lName;
int EmpAge;
double EmpSalary;
bool RecruitmentStatus;
};
void Employee::setSalary(const double& income)
{
this->EmpSalary += income;
}
void Employee::SetRecruitmentStatus(const bool& Status)
{
this->RecruitmentStatus = Status;
}
void Employee::Promote(const double& Promotion)
{
this->EmpSalary += Promotion;
}
template <typename T>
void displayElements(T& input)
{
for (auto iterator = input.begin();
iterator != input.end(); iterator++)
{
cout << *iterator << endl;
}
}
void selection(int&);
Employee getNewEmp(void);
int main()
{
vector<Employee> Records;
int ID;
do
{
selection(ID);
switch (ID)
{
case 1:
{
Records.push_back(getNewEmp());
break;
}
case 2:
{
cout << "please enter last name of the employee you want to change his/her recruitment'status: ";
string lastName; cin >> lastName; cout << endl;
auto memberLocation = find(Records.begin(), Records.end(), lastName.c_str());
break;
}
case 3:
{
cout << "please enter last name of the employee you want to promote his/her recruitment'salary: ";
string lastName; cin >> lastName; cout << endl;
auto memberLocation = find(Records.begin(), Records.end(), lastName.c_str());
break;
}
default:
{
if (ID !=4)
{
cout << "Wrong selection!\nThe program will be closed after a few seconds\n";
exit(1);
}
}
}
} while (ID != 4);
displayElements(Records);
cout << "Thanks for using this program\n";
return 0;
}
void selection(int& input)
{
system("cls");
cout << "please Choose one of these option:\n"
"1. add a new employee\n"
"2. changing an employee status\n"
"3. Promote an employee's salary\n"
"4. exit : ";
cin >> input;
}
Employee getNewEmp(void)
{
system("cls");
string firstName, lastName;
cout << "first name:"; cin >> firstName; cout << endl;
cout << "last name:"; cin >> lastName; cout << endl;
int age;
cout << "Age: "; cin >> age; cout << endl;
double salary;
cout << "Offered Salary: "; cin >> salary; cout << endl;
bool Status;
cout << "Is he/she working(1) or got fired(0) : "; cin >> Status; cout << endl;
return Employee(firstName, lastName, age, salary, Status);
}