Privacy Preservation for Friend-Recommendation Applications

Algorithm 4

Decryption.

: the number of attribute groups.

: the attribute group of recommended friends in

the form of plain-text( )

Input:

: the attribute group of recommended

friends in the form of cipher-text( );

: the attribute group’s key of user;

: the matching result ( );

Output:: all the attribute groups in the form of

plain-text( );

if 0 then

fordo

if then

end

end

end

return ;