We will count the words in all the input file flow as below input Assume there are two files each having a sentence Hello World Hello World (In file 1) Hello World Hello World (In file 2) Mapper : There would be each mapper for the a file For the given sample input the first map output: < Hello, 1> < World, 1> < Hello, 1> < World, 1> The second map output: < Hello, 1> < World, 1> < Hello, 1> < World, 1> Combiner/Sorting (This is done for each individual map) So output looks like this The output of the first map: < Hello, 2> < World, 2> The output of the second map: < Hello, 2> < World, 2> Reducer : It sums up the above output and generates the output as below < Hello, 4> < World, 4>
Output Final output would look like Hello 4 times World 4 times
