How can you differentiate between addition and condensation polymerization?

(N/A) Addition polymerization is the process of repeated addition of monomers possessing double or triple bonds to form polymers. For example,polythene is formed by the addition polymerization of ethene.
$n CH_2 = CH_2 \to -(CH_2 - CH_2)_n-$
Condensation polymerization is the process of formation of polymers by repeated condensation reactions between two different bi-functional or tri-functional monomers. $A$ small molecule such as water or hydrochloric acid is eliminated in each condensation step. For example,nylon $6,6$ is formed by the condensation polymerization of hexamethylenediamine and adipic acid.
$n H_2N(CH_2)_6NH_2 + n HOOC(CH_2)_4COOH \to [NH(CH_2)_6NHCO(CH_2)_4CO]_n + 2n H_2O$