We can now use map[key(i,j)]=value or map.find(key(i,j)) to operate on the map. Hash<pair<int,int>> depends on primitive and standard library types only. Am i remembering incorrectly, or did java, once upon a time, provide a pair class as part of its api?
Here is my object literal: The difference is that with std::pair you need to specify the types of both elements, whereas std::make_pair will create a pair with the type of the elements that are passed to it,. The main argument is that a class pair doesn't.
Every make_pair now becomes calling the inline key function. Just attempting this question i found in a past exam paper so that i can prepare for an upcoming java examination. Unordered map does not contain a hash function for a pair, so if we want to hash a pair then we have to explicitly provide it with a hash function that can hash a pair. This is a question about the interpretation of the compiler errors (and not a repeat question, as that.
What is a c#'s analog of std::pair in c++? This is easily worked around by defining your hash class outside of namespace std, and using that hash explicitly in. How can i add field key3 with value3 to the object? Provide a generic class pair for representing pairs of.