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This project implements a simple graph algorithm that needs two Map-Reduce jobs. A directed graph is represented as a text file where each line represents a graph edge.
20,40 represents the directed edge from node 20 to node 40.
Then, we group the nodes by their number of neighbors and for each group we count how many nodes belong to this group.
10 30 which says that there are 30 nodes that have 10 neighbors.