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std::forward_list::remove, remove_if

From cppreference.com
 
 
 
 
void remove( const T& value );
(since C++11)
(until C++20)
size_type remove( const T& value );
(since C++20)
template< class UnaryPredicate >
void remove_if( UnaryPredicate p );
(since C++11)
(until C++20)
template< class UnaryPredicate >
size_type remove_if( UnaryPredicate p );
(since C++20)

Removes all elements satisfying specific criteria. The first version removes all elements that are equal to value, the second version removes all elements for which predicate p returns true.

Contents

[edit] Parameters

value - value of the elements to remove
p - unary predicate which returns ​true if the element should be removed.

The expression p(v) must be convertible to bool for every argument v of type (possibly const) T, regardless of value category, and must not modify v. Thus, a parameter type of T&is not allowed, nor is T unless for T a move is equivalent to a copy (since C++11). ​

[edit] Return value

(none)

(until C++20)

The number of elements removed.

(since C++20)

[edit] Complexity

Linear in the size of the container

[edit] Example

#include <forward_list>
#include <iostream>
 
int main()
{
    std::forward_list<int> l = { 1,100,2,3,10,1,11,-1,12 };
 
    l.remove(1); // remove both elements equal to 1
    l.remove_if([](int n){ return n > 10; }); // remove all elements greater than 10
 
    for (int n : l) {
        std::cout << n << ' '; 
    }
    std::cout << '\n';
}

Output:

2 3 10 -1

[edit] See also

removes elements satisfying specific criteria
(function template) [edit]