std::map<Key,T,Compare,Allocator>:: rbegin, std::map<Key,T,Compare,Allocator>:: crbegin

Returns a reverse iterator to the first element of the reversed map . It corresponds to the last element of the non-reversed map . If the map is empty, the returned iterator is equal to rend() .

Parameters

(none)

Return value

Reverse iterator to the first element.

Complexity

Constant.

Notes

The underlying iterator of the returned reverse iterator is the end iterator . Hence the returned iterator is invalidated if and when the end iterator is invalidated.

libc++ backports crbegin() to C++98 mode.

Example

#include <iomanip>
#include <iostream>
#include <string_view>
#include <map>
 
int main()
{
    const std::map<int, std::string_view> coins
    {
        {10, "dime"},
        {100, "dollar"},
        {50, "half dollar"},
        {5, "nickel"},
        {1, "penny"},
        {25, "quarter"}
    }; // initializer entries in name alphabetical order
 
    std::cout << "US coins in circulation, largest to smallest denomination:\n";
    for (auto it = coins.crbegin(); it != coins.crend(); ++it)
        std::cout << std::setw(11) << it->second << " = ¢" << it->first << '\n';
}

US coins in circulation, largest to smallest denomination:
     dollar = ¢100
half dollar = ¢50
    quarter = ¢25
       dime = ¢10
     nickel = ¢5
      penny = ¢1

See also