#!/usr/bin/hopper
#include <batch-en.h>

/* main program */
begin
    ld=0
    set decimal '0'      // work with integers only
    prepare data(DATA)   // my dear "old" BASIC!
    get len data, move to 'ld'
    iter group ( --ld, ld, get data, perform(digital root), echo )
end

/* procedures */
.locals

func(digital root, n)
   c = 0, cnum=n
   iter group (++c, #(n>=10), s=0, q=0, m=n, \
       iter group ( m=q, #( m<>0 ),\
           #( q=int(m/10) ), #( s+= m-(q*10) ) ), n=s )
 /* put all into stack */
   #( lpad(".", 20, string(cnum) ) )
   " -> digital root = ", #(n+0),", (additive persistence = ",#(c+0),")"
back

DATA:
   data( 9992, 39390, 588225, 627615, 393900588225, 9837703004232342 )
   data( 126765060022822940, 199, 10 )
back