Difference between revisions of "Template:cpp/container/erase"
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{{cpp/container/note_iterator_invalidation|{{{1|}}}|erase}} | {{cpp/container/note_iterator_invalidation|{{{1|}}}|erase}} | ||
| − | The iterator {{tt|pos}} must be valid and dereferenceable. Thus the {{lc|end()}} iterator (which is valid, but is not | + | The iterator {{tt|pos}} must be valid and dereferenceable. Thus the {{lc|end()}} iterator (which is valid, but is not dereferenceable) cannot be used as a value for {{tt|pos}}. |
The iterator {{tt|first}} does not need to be dereferenceable if {{tt|first{{==}}last}}: erasing an empty range is a no-op. | The iterator {{tt|first}} does not need to be dereferenceable if {{tt|first{{==}}last}}: erasing an empty range is a no-op. | ||
Revision as of 10:45, 11 September 2020
| (1) | ||
iterator erase( iterator pos ); |
(until C++11) | |
| iterator erase( const_iterator pos ); |
(since C++11) | |
| (2) | ||
iterator erase( iterator first, iterator last ); |
(until C++11) | |
| iterator erase( const_iterator first, const_iterator last ); |
(since C++11) | |
Erases the specified elements from the container.
1) Removes the element at
pos.2) Removes the elements in the range
[first, last).| Information on iterator invalidation is copied from here |
The iterator pos must be valid and dereferenceable. Thus the end() iterator (which is valid, but is not dereferenceable) cannot be used as a value for pos.
The iterator first does not need to be dereferenceable if first==last: erasing an empty range is a no-op.
Contents |
Parameters
| pos | - | iterator to the element to remove |
| first, last | - | range of elements to remove |
Return value
Iterator following the last removed element.
If pos refers to the last element, then the end() iterator is returned.
If last==end() prior to removal, then the updated end() iterator is returned.
If [first, last) is an empty range, then last is returned.
Exceptions
| Templated information. See page source. |
Complexity
| Templated information. See page source. |
Example
Run this code
#include <{{{1}}}> #include <iostream> #include <iterator> void print_container(const std::{{{1}}}<int>& c) { for (auto &i : c) { std::cout << i << " "; } std::cout << '\n'; } int main( ) { std::{{{1}}}<int> c{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; print_container(c); c.erase(c.begin()); print_container(c); std::{{{1}}}<int>::iterator range_begin = c.begin(); std::{{{1}}}<int>::iterator range_end = c.begin(); std::advance(range_begin,2); std::advance(range_end,5); c.erase(range_begin, range_end); print_container(c); // Erase all even numbers (C++11 and later) for (auto it = c.begin(); it != c.end(); ) { if (*it % 2 == 0) { it = c.erase(it); } else { ++it; } } print_container(c); }
Output:
0 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 6 7 8 9 1 7 9
See also
| clears the contents (public member function of std::{{{1}}})
|
