Case study Reduce 1/ User' s reduce function class Adder public Reducer virtual void Reduce( Re duceInput*input)i / Iterate over all entries with the / same key and add the values int 64 value 0 while (!input-done()) value + stringToInt (input->value ())i input->Nextvalue ()i / Emit sum for input->key Emit(IntTostring(value)) REGISTER REDUCER(Adder)iCase Study 42 • Reduce