Printer and head unit

A printer comprising:

• a first head unit being elongate in a longitudinal direction,
• wherein the first head unit extends from a first end of the first head unit in the longitudinal direction to a second end of the first head unit in the longitudinal direction,
• the first head unit has a first nozzle group having a plurality of first nozzles arrayed with a first pitch along the longitudinal direction, and
• the first nozzle group is positioned between a center of the first head unit in the longitudinal direction and the second end of the first head unit in the longitudinal direction;
• and
• a second head unit being elongate in the longitudinal direction,
• wherein the second head unit extends from a third end of the second head unit in the longitudinal direction to a fourth end of the second head unit in the longitudinal direction,
• the second head unit has a second nozzle group having a plurality of second nozzles arrayed along the longitudinal direction,
• the second nozzle group is positioned between the third end of the second head unit in the longitudinal direction and a center of the second head unit in the longitudinal direction,
• the second nozzle group is positioned next to the first nozzle group in a transverse direction orthogonal to the longitudinal direction,
• the second nozzle group includes a plurality of nozzle sets,
• each of the plurality of the nozzle sets includes some of the plurality of second nozzles,
• the second nozzles in each of the plurality of the nozzle sets arrayed with the first pitch along the longitudinal direction,
• the plurality of the nozzle sets are arrayed with a second pitch along the longitudinal direction, and
• the second pitch is different from the first pitch.