END()

This function returns an iterator (or pointer, for arrays) that points one past the last element of a container, such as a vector, list, or array. This special position does not contain a valid element, but it marks the end boundary of the container, making it useful for iteration and comparisons. For example, in std::vector<int> v = {1, 2, 3};, v.end() points to the position just after 3. It is typically used with begin() in loops or algorithms, such as for (auto it = v.begin(); it != v.end(); ++it) or std::sort(v.begin(), v.end());. Since end() marks the stopping point rather than an element itself, dereferencing it is undefined behavior. Like begin(), C++11 introduced a generic std::end(container) function that works with both STL containers and raw arrays for consistent iteration.

#include <iostream>
#include <iterator>  // For std::begin() and std::end()
using namespace std;

int main() {
    // Declare and initialize a C++ array
    int numbers[] = {5, 10, 15, 20, 25};

    // Use std::begin() and std::end() to iterate through the array
    cout << "Array elements: ";
    for (auto it = begin(numbers); it != end(numbers); ++it) {
        cout << *it << " ";  // Dereference iterator to access each element
    }

    cout << endl;

    // You can also calculate the size of the array easily
    size_t arraySize = end(numbers) - begin(numbers);
    cout << "Array size: " << arraySize << endl;

    return 0;
}