[European Snake]

If you know your heading you can work the runway number by taking the third number off the heading. That gives you the number. Say your heading is 175, well thats 1 7_5 thus you would be landing on runway 17, and if there are two runways parallel both heading 175, you get runways 17L and 17R, and if there are three running parallel on 175, you have 17L 17C and 17R.