Answer 1

vectors in STL.. it enables u resizable arrays.
template < class T, class Alloc = allocator<T> > class vector; // generic template

#include <iostream>
#include <vector>

using namespace std;

int main()

{
    vector <int> g1;
    vector <int> :: iterator i;
vector <int> :: reverse_iterator ir;

    for (int i = 1; i <= 5; i++)
        g1.push_back(i);

    cout << "Output of begin and end\t:\t";

    for (i = g1.begin(); i != g1.end(); ++i)
 cout << *i << '\t';

    cout << endl << endl;

    cout << "Output of rbegin and rend\t:\t";

    for (ir = g1.rbegin(); ir != g1.rend(); ++ir)
 cout << '\t' << *ir;

    return 0;
}