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C++ Sets and Their Types

I am new to C++, and I am writing a breath first search. I would like to use a set to prevent from adding elements to a data structure that are already contained in that data structure. Thus I know a set is what I want. But besides that I understand sets in C++ yet.

I am having trouble figuring out what types a set can take on. Assume set is included as well as Vertex.h...

std::set<int> mySet;
mySet.insert(10);
// This works!

std::set<Vertex> mySet;
Vertex v;
mySet.insert(v);
// This Doesn't Work!

Can sets only take on primitive data types. Can you make a set hold an object type other than primitive objects?

ASKER CERTIFIED SOLUTION

Ichijo

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323k13l

ASKER

I tried to apply what you said but I think I am applying it wrong. I have a Vertex.h where methods are declared, and I have a Vertex.cpp where the methods are implemented. It the header file I put:

bool operator<(const Vertex& right) const

In the source file I put:

bool operator<(const Vertex& right) const {
return ._name < right._name; // _name is a int class-variable
}

What am I doing wrong here?

323k13l

ASKER

Nevermind, the only reason the above code did not work was because I left off the semicolon at the end of the declaration in the first code segment. Thank you for your help, Ichijo.