This method creates a "number line" of points starting and stopping individual ranges, then traverses the number line from minimum point upwards counting an occupancy of +1 for every range started, -1 for every range stopped.

The Code

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See: https://stackoverflow.com/questions/65812746/finding-all-common-ranges-finding-between-multiple-clients

Created on Wed Jan 20 17:28:44 2021

@author: Paddy3118