How to cross friends from Vkontakte and Facebook

To assign the arrow and let it intersect.

To use the API of these social services. networks.

in "Facebook" were added as a search for contacts from the "Vkontakte".

I mean to find all your Facebook friends from the contact and Vice versa? And how do You imagine that anyway?
Only chance is to compare e-mails, but Facebook does not email am find, and learn email-s friends too.
You can try to use advanced search according to parameters of the profile, but then you might get lucky but maybe not.

Recently wrote on Twitter that Facebook has opened two any apps that did import contacts or something.
Posomtrite they have in the ribbon: twitter.com/#!/vkontakte