/// <exception cref="System.IO.IOException"/>
            /// <exception cref="System.Exception"/>
            protected override void Reduce(Text key, IEnumerable <IntWritable> values, Reducer.Context
                                           context)
            {
                context.GetCounter("MyCounterGroup", "REDUCE_INPUT_GROUPS").Increment(1);
                int sum = 0;

                foreach (IntWritable val in values)
                {
                    sum += val.Get();
                }
                result.Set(sum);
                context.Write(key, result);
                context.GetCounter("MyCounterGroup", "REDUCE_OUTPUT_RECORDS").Increment(1);
            }