Re: STL set lower_bound
mattg <gara.matt@gmail.com> kirjutas:
On Mar 29, 2:24?pm, Paavo Helde <pa...@nospam.please.ee> wrote:
mattg <gara.m...@gmail.com> kirjutas:
[...]
void test(){
? ? ?s1.insert((new node(1)));
? ? ?s1.insert((new node(2)));
? ? ?s1.insert(new node(8));
? ? ?s1.insert(new node(9));
? ? ?s1.insert(new node(12));
[...]
? ? ?iter = s1.lower_bound(new node(5));
outputs
iter = 8
instead of
iter = 2
?
Because that's how lower_bound is defined:
"Returns an iterator to the first element in a set with a key that is
equ
al
to or greater than a specified key"
If you want the previous element, you can check the result against
s1.beg
in
() and decrement the iterator.
hth
Paavo
so something like:
if(iter != s1.begin())
{
node* lessthan = *(--iter); //this is the node less than the query
}
Yes, something like that. And I hope you are realizing you are leaking
memory all over the place, and the design would become much simpler by
using std::set<node>.
BEst regards
Paavo
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