Difference between revisions of "Template:cpp/container/back"
From cppreference.com
(make the example less cultural) |
(Be more precisely about undefined behavior.) |
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Returns reference to the last element in the container. | Returns reference to the last element in the container. | ||
| − | Calling {{tt|back}} on an empty container | + | Calling {{tt|back}} on an empty container causes undefined behavior [[cpp/language/ub|undefined behavior]]. |
| − | + | ||
===Parameters=== | ===Parameters=== | ||
(none) | (none) | ||
Revision as of 00:56, 28 December 2019
| reference back(); |
(since {std}) | |
| const_reference back() const; |
(since {std}) | |
Returns reference to the last element in the container.
Calling back on an empty container causes undefined behavior undefined behavior.
Contents |
Parameters
(none)
Return value
Reference to the last element.
Complexity
Constant.
Notes
For a container c, the expression return c.back(); is equivalent to { auto tmp = c.end(); --tmp; return *tmp; }
Example
The following code uses back to display the last element of a std::{{{1}}}<char>:
Run this code
#include <{{{1}}}> #include <iostream> int main() { std::{{{1}}}<char> letters {'a', 'b', 'c', 'd', 'e', 'f'}; if (!letters.empty()) { std::cout << "The last character is: " << letters.back() << '\n'; } }
Output:
The last character is f
See also
| access the first element (public member function of std::{{{1}}})
|
