procedure main(args)
   n := total := integer(args[1]) | 41		# Number of people
   k := count := integer(args[2]) | 3		# Count
   s := integer(args[3])-1 | 0                  # Number to save
   write("With ",n," people, counting by ",k,", the ",s+1," safe places are:")
   every write("\t",j(n,k,(n-s) to n))
end

procedure j(n,k,s)
   a := k*(n-s) + 1
   q := k/(k-1.0)
   nk := n*k
   olda := a
   while a <= nk do {
      olda := a
      a := ceil(a,q)
      }
   t := nk - olda
   return t
end

procedure ceil(a,q)
  n := a*q
  if n = integer(n) then return integer(n)
  n ?:= integer(tab(upto('.'))) + 1
  return n
end