need help with boolean operator

[johndw]

// Can anyone help solve this ??? I tried to use this example as the basis for training... however ...
// I receive the following errors at complie time :
/*
--------------------Configuration: person set 1 - Win32 Debug--------------------
Compiling...
person set 1.cpp
C:\j\hwc2\New Folder\person set 1.cpp(34) : error C2804: binary 'operator <' has too many parameters
C:\j\hwc2\New Folder\person set 1.cpp(35) : error C2804: binary 'operator ==' has too many parameters
Error executing cl.exe.
*/
// Could you help me to resolve this problem. ??? Please ???


#include <set>
#include <conio.h> // for using getch()
#include <string>
// #include <algorithm>
#include <iostream>
//#include <stdlib.h>

using namespace std;
//-------------------- using a multiset
class person
{
protected:
string Lname;
string Fname;

public:
person(): Lname(&quot;null&quot, Fname(&quot;null&quot {} //default ctr

person(string Ln, string Fn): Lname (Ln), Fname (Fn) {} //2 arg ctr

bool operator < (const person&, const person&);
bool operator == (const person&, const person&);

void display() const //output person data
{ cout << endl << Lname << &quot;, \t&quot; << Fname << &quot;, \t&quot; << endl; }

};

bool person:perator < (const person& p1, const person& p2) //operator for < comparison
{
if(p1.Lname == p2.Lname)
{ return(p1.Fname < p2.Fname) ? true : false; }
return(p1.Lname < p2.Lname) ? true : false;
}

bool person:perator == (const person& p1, const person& p2) //operator for == comparison
{
return(p1.Lname == p2.Lname && p1.Fname == p2.Fname) ? true : false;
}

//---------------------Now to make it happen. -------------
int main()
{
person p1(&quot;Smurf&quot;, &quot;Popa&quot;
person p2(&quot;Jojojo&quot;, &quot;Mojo&quot;
person p3(&quot;Willis&quot;, &quot;John&quot;
person p4(&quot;Willis&quot;, &quot;Jolene&quot;
person p5(&quot;Snow&quot;, &quot;Benjamin&quot;
person p6(&quot;MacDonald&quot;, &quot;Ronald&quot;
person p7(&quot;Silver&quot;, &quot;LongJohn&quot;
//created lots of instances to play with.

multiset<person, less<person> > persSet; //iterator to a multiset of persons -- I think ?
multiset<person, less<person> > ::iterator iter;

//put the people into the multiset
persSet.insert(p1);
persSet.insert(p2);
persSet.insert(p3);
persSet.insert(p4);
persSet.insert(p5);
persSet.insert(p6);
persSet.insert(p7);

cout << &quot;\nNumber of entries = &quot; << persSet.size();

iter = persSet.begin();
while (iter != persSet.end() )
(*iter++).display();

string searchLname, searchFname;
cout << &quot;\n\nEnter last name of person to search for : &quot;;
cin >>searchLname;
cout << &quot;\nEnter first name : &quot;;
cin >> searchFname;

//must create such a person's name to use in search
person searchPerson(searchLname, searchFname);


//count the number of occurances
int cntPersons = persSet.count(searchPerson);
cout << &quot;The number of people with that name is : &quot; << cntPersons;

//show all the names that match
iter = persSet.lower_bound(searchPerson);
while(iter != persSet.upper_bound(searchPerson))
(*iter++).display();
cout << endl;


getch ();
return 0;
}

 

[Zyrenthian]

bool person:perator < (const person& p1, const person& p2)

should be

bool person:perator < (const person& p1)
{
if(p1.Lname == p2.Lname)
{
return(p1.Fname < Fname) ? true : false;
}
return(p1.Lname < Lname) ? true : false;
}

 

[Zyrenthian]

sorry... submitted too early... still on my first cup o coffee. Follow this for all overloaded operators. You are comparing it with the current class so you dont need to have 2 parameters. Only one.

Matt

 

[johndw]

Thanks for the idea Matt.
I tried it but now I receive a different Microsoft error:
&quot;microsoft visual studio\vc98\include\functional(86) : error C2678: binary '<' : no operator defined which takes a left-hand operand of type 'const class person' (or there is no acceptable conversion)&quot; .
I'm still learning so maybe I compromised it some other way. (Like the way I applied it ?)Were you able to run the program with that change ???
I &quot;//&quot; commented out the other operator to narrow down the errors to just that one. I also received 4 warnings which I believe are related to the error.
Hope you can help.
-John