Difference between revisions of "Template:cpp/container/back"
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{{cpp/container/{{{1|}}}/title | back}} | {{cpp/container/{{{1|}}}/title | back}} | ||
{{cpp/container/{{{1|}}}/navbar}} | {{cpp/container/{{{1|}}}/navbar}} | ||
| + | {{#switch:{{{1|}}}|array= | ||
{{dcl begin}} | {{dcl begin}} | ||
| − | {{dcl | + | {{dcl rev begin}} |
| − | reference back(); | + | {{dcl | until=c++17| |
| + | reference back( size_type pos ); | ||
}} | }} | ||
| − | {{ | + | {{dcl | since=c++17| |
| + | constexpr reference back( size_type pos ); | ||
| + | }} | ||
| + | {{dcl rev end}} | ||
{{dcl rev begin}} | {{dcl rev begin}} | ||
| − | {{dcl | + | {{dcl | until=c++14 | |
| − | const_reference back() const; | + | const_reference back( size_type pos ) const; |
}} | }} | ||
{{dcl | since=c++14 | | {{dcl | since=c++14 | | ||
| − | constexpr const_reference back() const; | + | constexpr const_reference back( size_type pos ) const; |
}} | }} | ||
{{dcl rev end}} | {{dcl rev end}} | ||
| − | |{{dcl | since={{cpp/std|{{{1|}}}}}| | + | {{dcl end}} |
| + | |{{dcl begin}} | ||
| + | {{dcl | since={{cpp/std|{{{1|}}}}} | | ||
| + | reference back(); | ||
| + | }} | ||
| + | {{dcl | since={{cpp/std|{{{1|}}}}}| | ||
const_reference back() const; | const_reference back() const; | ||
}} | }} | ||
| − | + | {{dcl end}}}} | |
| − | {{dcl end}} | + | |
Returns reference to the last element in the container. | Returns reference to the last element in the container. | ||
Revision as of 20:35, 7 March 2016
| 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 is undefined.
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 {'o', 'm', 'g', 'w', 't', '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}}})
|
