Patent ID: 8020844

Claim:
A printer comprising: an offset-stacking sheet discharge mechanism adapted to discharge sheets to a plurality of stack positions; a setting acceptor configured to accept a set of printing settings for a current printing job to print a total number of sheets corresponding to a designated number of copy sets, including a setting of a first printing condition involving a confirmation print to print a single copy set consisting of a given number of sorted pages before a temporary pause waiting for a continuation instruction to print the total number of sheets, and a setting of a second printing condition involving a sorting print to print the designated number of copy sets each consisting of the given number of sorted pages to thereby print the total number of sheets; and a controller configured to store therein a last stack position in a previous printing job, as a first stack position, and adapted, as the set of printing settings accepted by the setting acceptor has a first subset thereof including the setting of the first printing condition and the setting of the second printing condition, to discharge sheets in the confirmation print in the first subset of the set of printing settings to a second stack position offset from the first stack position, and after acceptance of the continuation instruction for the first subset of the set of printing settings, discharge sheets of the designated number of copy sets in the sorting print in the first subset of the set of printing settings to an alternating stack position alternating every copy set between the first and second stack positions, starting from the second stack position.