Initialization:

#include  <vector>
#include  <stdexcept>
...
typedef std::vector<int> IntVector; 
...
size_t size = 3;
IntVector array(size);

Access:

// No bound controll: Access to uninitialized memory !!
// for (unsigned int i = 0; i < (size + 1); i++) {
//     array[i] = i;
// }
 
// Bound control -> vector::_M_range_check
for (unsigned int i = 0; i < (size + 1); i++) {
    try {
        array.at(i) = i;
    } catch(std::out_of_range e) {
        std::cout << e.what() << std::endl; 
    }
}
// array.size() = 3; array.capacity = 3;

Add:

// Add elements beyond the initial size
array.push_back(9);
 
// array.size() = 4; array.capacity = 6;
for (unsigned int i = 0; i < array.size(); i++) {
    std::cout << array[i] << std::endl; // {0, 1, 2, 9}
}

From C arrays to C++ Vector:

int p[] = {1, 2, 3, 4, 5};
IntVector a(p, p+5);
 
for (unsigned int i = 0; i < a.size(); i++) {
    std::cout << a[i] << std::endl; // {1, 2, 3, 4, 5}
}

Iterator:

IntVector vector;
IntVector::const_iterator i;
 
vector.push_back(1);
vector.push_back(2);
vector.push_back(3);
 
for (i = vector.begin(); i != vector.end(); i++) {
    std::cout << "(*i)" << (*i) << std::endl;
}