Screenplay: `std::vector`, And Pointer Arithmetics¶

Using raw C pointers

code/vector-basic-pointer-arith.cpp¶

#include <vector>
#include <iostream>
   
int main()
{
    std::vector<int> a = {100, 200, 300};

    const int *begin = &a[0];              // <--- pointer to first element
    const int *end = &a[3];                // <--- pointer past last element

    while (begin != end)
        std::cout << *begin++ << std::endl;

    return 0;
}

Generalized pointer: STL iterator

.begin(), .end()

code/vector-basic-iterators.cpp¶

#include <vector>
#include <iostream>
   
int main()
{
    std::vector<int> a = {100, 200, 300};

    std::vector<int>::const_iterator begin = a.begin();  // <--- looks like a pointer, but isn't
    std::vector<int>::const_iterator end = a.end();      // <--- looks like a pointer, but isn't

    while (begin != end)
        std::cout << *begin++ << std::endl;

    return 0;
}

Simpler alternative, but not always applicable: range based for

code/vector-basic-range-based.cpp¶

#include <vector>
#include <iostream>
   
int main()
{
    std::vector<int> a = {100, 200, 300};
    for (int i: a)                           // <--- range based for
        std::cout << i << std::endl;
    return 0;
}

Screenplay: std::vector, And Pointer Arithmetics¶

Screenplay: `std::vector`, And Pointer Arithmetics¶