New Topic/Question
Reply
Here is the assignment description: "overload the >> and << operators for the
Person class. Let pObj be a Person object, the overloaded >> operator will allow one to use
the following command to receive a specific value for each data member in pObj:
cin >> pObj;
The overloaded << operator on the other hand will allow one to use the following command
to print out all the data members of pObj on the screen.
cout << pObj;"
I got my code here, i am not sure my implementation for overloading << and >> is right or wrong. And I think i have to do something for the driver file main(),but i do not know how. Please give me some hints.Here is my code. I used different color for overloading the operator >> and <<:
#ifndef _PERSON_H
#define _PERSON_H
#include <iostream>
#include <string>
#include <iomanip>
#include <cstdlib>
using namespace std;
struct Date
{
int day;
int month;
int year;
};
class Person
{
private:
string fname;
string lname;
string ssn;
int age;
Date birthDay;
double salary;
double *grades;
int num_grades;
public:
//constructors
Person();
Person(string firstname, string lastname, string the_ssn, int the_age, Date the_birthDay, double the_salary, int the_num_grades);
//overloading << and >>
friend ostream& operator<<(ostream& output, const Person& pObj);
friend istream& operator>>(istream& input, Person& pObj);
//big three
Person(const Person & aperson); //copy constructor
void operator=(const Person &rhs); //assigment operator
~Person();//destructor
void quick_sort(int left, int right); //sorts the grades
//mutator
void setFname(string firstname);
void setLname(string lastname);
void setSSN(string SSN);
void setAge(int Age);
void setBirthDay(Date Birthday);
void setDay(int Day);
void setMonth(int Month);
void setYear(int year);
void setSalary(double Salary);
void add_grade(double hw_grd);
void update_grade(int i, double new_val);
//accessor
string getFname();
string getLname();
string getSSN();
Date getBirthday();
int getAge();
int getDay();
int getMonth();
int getYear();
double getSalary();
double get_a_grade(int i);
void print_grades();
int get_num_grades();
};
//randomly get students' information except for name
void init_Person(Person& person, string fname, string lname, int num_grades);
string randomStrGen(int length);//randome string generator
int randomIntGen(int lowest, int highest);//random integer generator
double randomDoubleGen(double XMin, double XMax);//random double generator
void output(Person student[], int StudentNumber);//function to print out data
#endif
#include "person.h"
//default constructor
Person::Person()
{
fname = "na";
lname = "na";
ssn = "na";
age = 0;
birthDay.day = 0;
birthDay.month = 0;
birthDay.year = 0;
salary = 0;
num_grades = 0;
grades = NULL;
}
//stores the data
Person::Person(string firstname, string lastname, string the_ssn, int the_age, Date the_birthDay, double the_salary, int the_num_grades)
{
fname = firstname;
lname = lastname;
ssn = the_ssn;
age = the_age;
birthDay.day = the_birthDay.day;
birthDay.month = the_birthDay.month;
birthDay.year = the_birthDay.year;
salary = the_salary;
num_grades = the_num_grades;
grades = NULL;
}
//copy the student data~construct a new object as a copy of "aperson"
Person::Person(const Person & aperson)
{
fname = aperson.fname;
lname = aperson.lname;
ssn = aperson.ssn;
age = aperson.age;
birthDay.day = aperson.birthDay.day;
birthDay.month = aperson.birthDay.month;
birthDay.year = aperson.birthDay.year;
salary = aperson.salary;
if(num_grades == 0)
grades = NULL;
else
grades = new double[num_grades];
for( int i = 0; i < num_grades; i++)
grades[i] = aperson.grades[i];
}
//assigment operator
void Person::operator=(const Person &rhs)
{
fname = rhs.fname;
lname = rhs.lname;
ssn = rhs.ssn;
age = rhs.age;
birthDay.day = rhs.birthDay.day;
birthDay.month = rhs.birthDay.month;
birthDay.year = rhs.birthDay.year;
salary = rhs.birthDay.year;
if(num_grades > 0)
delete [] grades;
num_grades = rhs.num_grades;
grades = new double[num_grades];
for(int i = 0; i < num_grades; i++)
grades[i] = rhs.grades[i];
}
//destructor-return the memory
Person::~Person()
{
if(grades != NULL)
{
delete [] grades;
grades = NULL;
}
}
//mutators
void Person::setFname(string firstname)
{
fname = firstname;
}
void Person::setLname(string lastname)
{
lname = lastname;
}
void Person::setSSN(string SSN)
{
ssn = SSN;
}
void Person::setAge(int Age)
{
age = Age;
}
void Person::setBirthDay(Date Birthday)
{
birthDay.day = Birthday.day;
birthDay.month = Birthday.month;
birthDay.year = Birthday.year;
}
void Person::setDay(int Day)
{
birthDay.day = Day;
}
void Person::setMonth(int Month)
{
birthDay.month = Month;
}
void Person::setYear(int Year)
{
birthDay.year = Year;
}
void Person::setSalary(double Salary)
{
salary = Salary;
}
//sets the grade
void Person::add_grade(double hw_grd)
{
//if empty,allocate one new double
if (num_grades == 0)
{
grades = new double [1];
//verity it is scuscessful
if(grades == NULL) {
cerr << "Copy constructor: memory allocation error (1)!\n";
return;
}
grades[0] = hw_grd;
}
else //resizing, increase the size of array by 1
{
double *temp_grades = new double[num_grades];
if(temp_grades == NULL){
cerr << "Copy constructor: memory allocation error (2)!\n";
return;
}
for (int i=0; i<num_grades; i++) //save the grades
temp_grades[i] = grades[i];
delete [] grades;
grades = new double [num_grades+1]; //expand the list by one
//verify the above allocation
if (grades == NULL ){
cerr << "Copy constructor: memory allocation error (3)!\n";
return;
}
for ( int i=0; i<num_grades; i++)
grades[i] = temp_grades[i]; //copy the existing grades
grades[num_grades] = hw_grd; // add the new grade
delete [] temp_grades;
}
num_grades +=1;
}
//keep track the grades
void Person::update_grade(int i, double new_val)
{
if(i > 0 && i <= num_grades)
{
grades[i-1] = new_val;
}
}
//prints out the grade
void Person::print_grades()
{
if(num_grades > 0)
{ //setprecision(2) reduce the decimal numbers
for( int i = 0; i < num_grades; i++){
cout << setprecision(2) << grades[i] << " ";}
cout << endl;
cout << fixed;
}
}
//accessors
string Person::getFname()
{
return fname;
}
string Person::getLname()
{
return lname;
}
string Person::getSSN()
{
return ssn;
}
int Person::getAge()
{
return age;
}
Date Person::getBirthday()
{
return birthDay;
}
double Person::getSalary()
{
return salary;
}
int Person::getDay()
{
return birthDay.day;
}
int Person::getMonth()
{
return birthDay.month;
}
int Person::getYear()
{
return birthDay.year;
}
double Person::get_a_grade(int i)
{
if(i>0 && i <= num_grades)
return grades[i-1];
else
return -1;
}
int Person::get_num_grades()
{
return num_grades;
}
//get random information for student except for names
void init_Person(Person& person, string fname, string lname, int num_grades)
{
person.setFname(fname);//assign the name to the person
person.setLname(lname);
person.setSSN(randomStrGen(9));//assign ssn
person.setAge(randomIntGen(15, 90));//assign age
Date birthday;
birthday.month = randomIntGen(1, 12); //random month 1-12
birthday.day = randomIntGen(1, 31);//random day 1-31
birthday.year = 2010 - (int)person.getAge();//get the year by age
person.setBirthDay(birthday);
person.setSalary(randomDoubleGen(0.0, 100000.0));//random salary in 0-100000
for(int i = 0; i < num_grades; i++)
{
person.add_grade(randomDoubleGen(0, 100)); //randomly get grades in 0-100
}
person.print_grades(); //print out the grades
person.quick_sort(0, num_grades-1); //sort the grades
}
//quick sort, sort the grades
void Person::quick_sort(int left, int right)
{
int i = left, j = right;
double temp;
double pivot;
pivot = grades[(left + right)/2];
//partition
while ( i <= j){
while (grades[i] < pivot)
i++;
while (grades[j] > pivot)
j--;
if( i <= j){
temp = grades[i];
grades[i] = grades[j];
grades[j] = temp;
i++;
j--;
}
}
//recursion
if (left < j)
quick_sort(left, j);
if (i < right)
quick_sort(i, right);
}
//random String function
string randomStrGen(int length)
{
static string charset = "1234567890"; //set string only random in this range
string result;
result.resize(length);
for (int i = 0; i < length; i++) //using loop to randomly get 9 letters (digits)
result[i] = charset[rand() % charset.length()];
return result;
}
//random Integer function
int randomIntGen(int lowest, int highest)
{
int I = lowest + rand() % (highest - lowest + 1);
return I;
}
//random Double function
double randomDoubleGen(double XMin, double XMax)
{
double range = XMax - XMin;
double num = static_cast<double>(rand()) * range / static_cast<double>( RAND_MAX ) + XMin ;
return num;
}
//Print out the information
void output(Person student[], int StudentNumber)
{
for(int i = 0; i < StudentNumber; i++)
{
cout << "Name:" << student[i].getFname() << " ";
cout << student[i].getLname() << endl;
cout << "SSN:" << student[i].getSSN() << endl;
cout << "Age:" << student[i].getAge() << endl;
cout << "Salary:$" <<setprecision(2) << fixed <<student[i].getSalary() << endl;
Date birthday;
birthday = student[i].getBirthday();
cout << "Date of Birth: " << (int)birthday.month << "-";
cout << (int)birthday.day << "-";
cout << birthday.year << endl;
cout << "Grades:";
student[i].print_grades();
cout << endl;
}
}
===========================================================
//Need help here!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
ostream& operator<<(ostream& output,const Person& pObj)
{
output << "Name: "<< pObj.fname<<" "<<pObj.lname <<endl;
output << "SSN:" <<pObj.ssn << endl;
output << "Age: " <<pObj.age << endl;
output << "Salary:$" <<setprecision(2) << fixed <<pObj.salary << endl;
output << "Date of birth: "<< pObj.birthDay.month << "-";
//Date birthday;
//birthday = pObj.birthDay;
//output << "Date of Birth: " <<(int)birthday.month << "-";
//output << pObj.birthday.day << "-";
//output << pObj.birthday.year << endl;
output << pObj.birthDay.day << "-";
output << pObj.birthDay.year << endl;
for (int i = 0; i <pObj.num_grades;i++)
output << "Number Of grades" << i << " :"<<pObj.grades[i]<<endl;
return output; //returns a reference
}
//uses iostream and cstdlib
istream& operator>>(istream& input, Person& pObj)
{
int NumberOfStudent;
input >> NumberOfStudent;
input >> pObj.fname >> pObj.lname;
return input;
}
#include "person.h"
int main()
{
int StudentGrades;
string firstname, lastname;
int NumberOfStudent;
cout << "How many SFSU students?" << endl;
cin >> NumberOfStudent;
Person *person;
person = new Person[NumberOfStudent];
if( NumberOfStudent >= 1)
{
cout<< "Please enter student's first name & last name: " << endl;
cout << "(Separate them by space)" << endl;
cin >> firstname >> lastname;
cout << "Please also enter number of grades for this student: " << endl;
cin >> StudentGrades;
init_Person(person[0], firstname, lastname,StudentGrades);//initial first student
cout << endl;
//get more for more students
for (int i = 1; i < NumberOfStudent; i++)
{
cout << "Please enter next student's first name & last name:\n";
cin >> firstname >> lastname;
cout << "Please also enter number of grades for this student: " << endl;
cin >> StudentGrades;
init_Person(person[i], firstname, lastname,StudentGrades);//initalize them
cout << endl;
}
}
cout << endl;
cout << "Print out the student information randomly and sorted the grades: " << endl;
output(person,NumberOfStudent);//print out the information
return 0;
}
This post has been edited by JohnnyBoy: 11 November 2010 - 12:23 AM
MultiQuote
| 