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Input comparison problem

TheRefus (7)
I am still very new at c++ and coding in general. I am working on an assignment for my class and I think I am running into the "phantom newline" problem. I have already inserted cin.ignore() but the identical(to my knowledge!) char arrays are not qualifying as equal to when I put in the same name. Maybe I have something wrong with my == operator, but I am stumped at this point, and any help will be greatly appreciated. I am only able to use char arrays, not strings.

Relevant code:

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#include "stdafx.h"
#include <iostream>
#include <istream>
using namespace std;

class Student
{
private:
	long ssn;
	char name[80];
public:
	Student();
	Student(char name[80], long ssn);
	Student(Student&);
	void setSSN(long);
	long getSSN();
	void setName(char *);
	const char* getName();
	bool operator==(Student&);
	Student operator=(Student&);
};

Student::Student()
{
	//Default Constructor, no arguments
	strcpy_s(name, sizeof(name), "unassigned");
	ssn = 999999999;
}

long Student::getSSN()
{
	//Retrieves the Student's SSN
	return ssn;
}

const char* Student::getName()
{
	//Retrieves the Student's name
	return name;
}

void Student::setSSN(long newSSN)
{
	//Applies the new SSN to the student
	if (newSSN > 0)
		ssn = newSSN;
}

void Student::setName(char* newName)
{
	//Applies the new Name to the student
	if (strlen(newName) > 0)
		strcpy_s(name, sizeof(name), newName);
}

bool Student::operator==(Student& cStu)
{
	//Equality operator
	if (ssn == cStu.getSSN() && name == cStu.getName())
		return true;
	else
		return false;
}

int main()
{
	//Creates the 2 students and tests operators

	char n[80];
	long s;
	Student stu1;
	Student stu2;


	cout << "\nEnter student 1 name: ";
	cin.getline(n, 80); stu1.setName(n);
	cout << "Enter student 1 ssn: ";
	cin >> s; cin.ignore(); stu1.setSSN(s);
	cout << "\nEnter student 2 name: ";
	cin.getline(n, 80); stu2.setName(n);
	cout << "Enter student 2 ssn: ";
	cin >> s; stu2.setSSN(s);
	

	if (stu1 == stu2)
		cout << "Those are the same students" << endl << endl << endl;
	else
		cout << "Those are not the same students" << endl << endl << endl;


	return 0;
}
Last edited on
Peter87 (11234)
Use std::strcmp to compare two C strings. The == operator compares if the pointers point to the same location in memory and that isn't what you want.
http://www.cplusplus.com/reference/cstring/strcmp/
TheRefus (7)
My new line 59 is

if ((ssn == cStu.getSSN()) && (strcmp(name, cStu.getName())=0))

But I am now getting the 'modifiable lvalue' for this line. Am I using strcmp correctly?
Last edited on
wildblue (1505)
strcmp(name, cStu.getName())=0 <- did you mean that to be == ?
TheRefus (7)
Ah that was it! Can't believe I overlooked that. Thank you both very much.
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