Question

I hav two stl maps like map<int,int> and i want to compare them.. so here is the code..

map <int, int> a,b;
insert into a and b;
map<int,int>::iterator i;

for(i=a.begin();i!=a.end();i++){
    if(what should be here?)
         then cout << (*i).first << " also present in b" << endl;
}

I was hoping that something like (b[(*i).first]).exist??

Answer 1

Use map::find as:

for(i=a.begin(); i!=a.end(); i++)
{
  if( b.find(i->first) != b.end() )
       std::cout << (*i).first << " also present in b" << std::endl;
}

Note i->first and (*i).first are same.