Homework Requirements:

Please download the dataset named "data.csv$"$ from the link above. In this dataset, each line is a pair of strings separated with comma. Formally, each line can be represented as $(c_1,c_2).$

Problem Details:

Given the pairs in the "data.csv$"$ dataset, please write a MapReduce program according to the following requirements.

Map phase:

Order the pair of strings alphabetically.

For example, given a pair $(c_1,c_2),$

if $c_1{c}_2,$ then the ordered pair is still $(c_1,c_2)$;

if $(c_2,c_1)c_2,$ then the ordered pair $is(c_2,c_1)$;

Reduce phase:

Output all ordered pairs $in$ the dataset $as$ well $as$ the count $of$ each ordered pair.

$In$ addition, please use counter $to$ compute the total number $of$ unique ordered pairs.