Processes all those intermediate key-value pairs generated by Mapper or combined by Combiner to aggregate, perform calculations or apply different operations to produce the reduced output.
public interface IReducer : IDisposable
This method will provide the user with a starting point to initialize any parameters you want to be used before the actual reducing of elements begins.
This method will provide the task with the final result of the map reduce operation for specific intermediate key/value pair.
This method will reduce (process) the intermediate key-value pairs into further meaningful pairs.
If the workflow diagram is referred, it means that the values of the grouped elements from Combiner are summed up to find the actual word count.