In the video we have overloaded the () operator. I don’t really understand why we have done that. Please explain
Regarding overloading ()
hi @abhi_11,
here we are defining our own class(Student) but using the default map, so we need to tell the hash map how to make the hashing of the data we are providing as its not known to the compiler beforehand.
So this is done by passing the HashFn here which overloaded () operator. So whenever the map will insert anything it will use that hashing function
hope this clears the doubt 
hi, I know that we have defined our custom student class and using STL’s map but why we have to overload the () operator. Why can’t we just pass the HashFn as we usually do. For example in sort() and priority queue STL, we just provide comparator function.
@abhi_11, have you done it using custom class in priority queue its done same way
read here : https://www.geeksforgeeks.org/stl-priority-queue-for-structure-or-class/
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