00p10p20p30p                                 v
current total in 0,0 top3 in 1,0 2,0 and 3,0
>#;~:a-#v_$v@,a.++g03g02g01 ;                >
^+*a\-0'<  : if not an empty line, add to total and read another number
^   p00+g00_v      >10g00g10p00pv      >20g00g20p00pv      >00g30pv
^  vp01<    >10g00gw>           >20g00gw            >30g00gw      >00p
                   >            ^      >            ^      >      ^