Question

I have a deque:

deque<char> My_Deque;
My_Path.push_front('a');
My_Path.push_front('b');
My_Path.push_front('c');
My_Path.push_front('d');
My_Path.push_front('e');

There are such ways to output it.

The first:

deque<char>::iterator It;
for ( It = My_Deque.begin(); It != My_Deque.end(); It++ )
    cout << *It <<  " ";

The second:

for (i=0;i<My_Deque.size();i++) {
    cout << My_Deque[i] <<  " ";
}

What is the best way to access deque’s element – through iterator or like this: My_Deque[i]?
Has a deque<…> element an array of pointers to each element for fast access to it’s data or it provides access to it’s random element in consequtive way (like on a picture below)?

Answer 1

An STL deque is usually implemented as a dynamic array of fixed-size arrays, so indexed access is perfectly efficient.