NAME¶

std::basic_string::back - std::basic_string::back

Synopsis¶

CharT& back(); (1) (constexpr since C++20)
const CharT& back() const; (2) (constexpr since C++20)

Returns reference to the last character in the string. The behavior is undefined if
empty() is true.

Parameters¶

(none)

Return value¶

Reference to the last character, equivalent to operator[](size() - 1).

Complexity¶

Constant.

Notes¶

In libstdc++, back() is not available in C++98 mode.

Example¶

// Run this code

#include <iostream>
#include <string>

int main()
{
std::string s("Exemplary");
char& back1 = s.back();
back1 = 's';
std::cout << s << '\n'; // "Exemplars"

std::string const c("Exemplary");
char const& back2 = c.back();
std::cout << back2 << '\n'; // 'y'
}

Output:¶

Exemplars
y

Defect reports

The following behavior-changing defect reports were applied retroactively to
previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 534 C++98 std::basic_string did not have the member added
function back()

See also¶

front accesses the first character
(DR*) (public member function)
back accesses the last character
(public member function of std::basic_string_view<CharT,Traits>)