Optimal Solicitors Tech Test - 
A C# application that asks the user to provide two post codes and then calculates the distance between them
Usage
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Notes
This solution uses the Google Maps Distance Matrix API to show the user the distance between two UK postcodes, it assumes that the user would be driving. If I was going to improve it I would include a switch statement and prompt the user to select if they are driving, walking or cycling to their destination, since each would have a slightly different distance.