what order are results returned in ?!

I get it, there are 10 countries therefore 10 results, but in what order are the results returned? Do we scan by rows from the top down or what ? How does the answer shown (if it is the answer to the 10 country problem in the example) relate the to the colours ? What defines country zero on the map ? (top left ?). If i scan the map from top left i get the following answer to the example: 1,3,2,4,1,3,2,4,2,1.