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Regarding the C++ STL map, erasing by key:-
size_type map::erase ( const key_type& x ); Is it legal to erase a non-existing key? i.e. is the snippet below ok?
map<char,int> mymap; mymap['c']=30; mymap.erase('c'); mymap.erase('c'); mymap.erase('D'); Cheers
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To delete a key from a map, we can use Go's built-in delete function. It should be noted that when we delete a key from a map, its value will also be deleted as the key-value pair is like a single entity when it comes to maps in Go.
Using erase() : erase() is used to erase the pair in map mentioned in argument, either its position, its value or a range of number. erase(key) : Erases the key-value pair using key mentioned in its argument.
map::erase() is a built-in function in C++ STL which is used to erase element from the container. It can be used to erase keys, elements at any specified position or a given range. Parameters: The function accepts one mandatory parameter key which specifies the key to be erased in the map container.
The standard approach to remove elements from a map is using the std::map::erase member function. It offers several overload versions. The first overload version accepts an iterator pointing to an element that needs to be removed from the map.
Yes, in fact, std::map::erase() returns a size_type which indicates the number of keys erased. Thus it returns 0 for nothing erased and 1 for something erased for a map.
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