proposition: Lemma Z_of_intK : cancel Z_of_int int_of_Z.
proof: Proof. case=> [[|n]|n] //=. congr Posz; lia. rewrite addnC /=; congr Negz; lia. Qed.
imports: Coq(ZArith) HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(div choice fintype tuple finfun bigop finset prime) mathcomp(order binomial ssralg countalg ssrnum ssrint) mathcomp(zify_ssreflect)