std::experimental::erase_if(std::map)
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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, seestd::erase_if(since C++20) |
Defined in header <experimental/map> | ||
template<class Key,class T,class Compare,class Alloc,class Pred> void erase_if(std::map<Key, T, Compare, Alloc>& c, Pred pred); | (library fundamentals TS v2) | |
Erases all elements that satisfy the predicatepred 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/map>#include <iostream> template<typename Os,typename Container>inline Os& operator<<(Os& os, Containerconst& cont){ os<<'{';for(constauto& item: cont) os<<'{'<< item.first<<", "<< item.second<<'}';return os<<'}';} int main(){std::map<int,char> data{{1,'a'},{2,'b'},{3,'c'},{4,'d'},{5,'e'},{4,'f'},{5,'g'},{5,'g'}};std::cout<<"Original:\n"<< data<<'\n'; std::experimental::erase_if(data,[](constauto& item){return(item.first&1)==1;});std::cout<<"Erase items with odd keys:\n"<< data<<'\n';}
Output:
Original:{{1, a}{2, b}{3, c}{4, d}{5, e}}Erase items with odd keys:{{2, b}{4, d}}[edit]See also
| removes elements satisfying specific criteria (function template)[edit] |
