Re: STL set lower_bound

From:

mattg <gara.matt@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Sun, 29 Mar 2009 16:07:22 -0700 (PDT)

Message-ID:

<4dae89bf-0d4c-4749-960a-6fcfc38b8596@p42g2000prp.googlegroups.com>

On Mar 29, 3:31 pm, Paavo Helde <pa...@nospam.please.ee> wrote:

mattg <gara.m...@gmail.com> kirjutas:

in my actual application I clean up. My original attempt at this was
using node as a struct instead of a class but I couldn't figure out
how to write the line

iter = s1.lower_bound(new node(5));

I would write this example as:

#include<iostream>
#include<set>

using namespace std;

class node {
private:
        int val;
public:
        node(int v){
                val = v;
        }
        int GetVal() const {
                return val;
        }
        bool operator<(const node& b) const {
                return val<b.val;
        }

};

set<node> s1;

void test(){
        s1.insert(1);
        s1.insert(2);
        s1.insert(8);
        s1.insert(9);
        s1.insert(12);

}

int main(){
        test();
        set<node>::iterator iter;

        iter = s1.lower_bound(5);
        cout << "iter =" << iter->GetVal() << endl;

}

Ahh ok, thats much cleaner, but I have 2 questions:

1) does this design not cause any memory leaks
2) if I add to the node

class node {
private:
        int val;
        int val2;
public:
        node(int v){
                val = v;
                val2 = 0;
        }
        int GetVal() const {
                return val;
        }
        int Do() {
                val2++;
        }
        bool operator<(const node& b) const {
                return val<b.val;
        }

};

and I try calling iter->Do() I get error

test.cpp:80: error: passing 'const node' as 'this' argument of 'void
node::Do()' discards qualifiers

How would I work around this?