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std::ranges::common_view<V>::begin

constexpr auto begin();
 (1) (since C++20) 
constexpr auto begin() const requires range<const V>;
 (2) (since C++20)
1) Returns an iterator to the first element of the common_view, that is: Here base_ (the name is for exposition only purposes) is the underlying view.
2) Same as (1), but V is const-qualified.

Parameters

(none).

Return value

An iterator to the beginning of the underlying view.

Example

#include <iostream>
#include <numeric>
#include <ranges>
#include <string_view>
 
int main()
{
    constexpr auto common = std::views::iota(1)
                          | std::views::take(3)
                          | std::views::common
                          ;
 
    for (int i{}; int e : common) { std::cout << (i++ ? " + " : "") << e; }
 
    std::cout << " = " << std::accumulate(common.begin(), common.end(), 0) << '\n';
}

Output:

1 + 2 + 3 = 6

See also

(C++20)
 returns an iterator to the end
(public member function)
(C++20)
 returns an iterator to the beginning of a range
(customization point object)
(C++20)
 returns a sentinel indicating the end of a range
(customization point object)

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