std::experimental::erase_if (std::set)
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Merged into ISO C++ The functionality described on this page was merged into the mainline ISO C++ standardas of 11/2018, see std::erase_if (since C++20)
Defined in header
<experimental/set>
template< class Key, class Compare, class Alloc, class Pred >
void erase_if( std::set <Key, Compare, Alloc>& c, Pred pred );
(library fundamentals TS v2)
void erase_if( std::set <Key, Compare, Alloc>& c, Pred pred );
Erases all elements that satisfy the predicate pred from the container. Equivalent to
for (auto i = c.begin(), last = c.end(); i != last;) { if (pred(*i)) i = c.erase(i); else ++i; }
Contents
[edit] Parameters
c
-
container from which to erase
pred
-
predicate that determines which elements should be erased
[edit] Complexity
Linear.
[edit] Example
Run this code
#include <experimental/set> #include <iostream> template<typename Os, typename Container> inline Os& operator<<(Os& os, Container const& container) { os << "{ "; for (const auto& item : container) os << item << ' '; return os << '}'; } int main() { std::set <int> data{3, 3, 4, 5, 5, 6, 6, 7, 2, 1, 0}; std::cout << "Original:\n" << data << '\n'; auto divisible_by_3 = [](auto const& x) { return (x % 3) == 0; }; std::experimental::erase_if(data, divisible_by_3); std::cout << "Erase all items divisible by 3:\n" << data << '\n'; }
Output:
Original:
{ 0 1 2 3 4 5 6 7 }
Erase all items divisible by 3:
{ 1 2 4 5 7 }