Retreive result of 2 variables

Hello,

I am struggling to write the code to retreive the intersection cell of 2 dynamic entries:

Lets say I have a table with:
Milan Berlin Bruxelles Paris
Milan
Berlin
Bruxelles
Paris
With the distances at intersection
How can I retreive the distance for each user choosing one city in a row and one city in a column?

Any help would be great!!