3 CuFeS2-II + 16 HNVO3 3 Fe(NVO3)2 + 3 Cu(NVO3)2 + 6 S0 + 4 NIIO + 8 H2O

This is an oxidation-reduction (redox) reaction:

6 S-II - 12 e- 6 S0 (oxidation)

4 NV + 12 e- 4 NII (reduction)

Change the oxidation states