Hi there,

I have 2 columns of text which include the origins and destinations of an airline and I want to count the number of unique routes (ie. A to B and B to A should count as one).

If the network was simple, and the destinations for each airport were the same as its origin airports, it's simple (I just count the number of total routes and halve it). But in this case, an airport "A" might have a flight to "B" and then the plane goes to "C" before returning to "A" - so I can't assume that "A" and "B" connect in both directions.

Can anyone help? Would be really appreciated