externalintegerfn  search(integer  start, finish, char)
  while  start <= finish cycle 
    result  = start if  byteinteger(start) = char
    start = start + 1
  repeat 
  result  = 0
end 

external  integer  fn  search back(integer  start, finish, char)
  while  start <= finish cycle 
    result  = finish if  byteinteger(finish) = char
    finish = finish - 1
  repeat 
  result  = 0
end 

external  integer  fn  count(integer  start, finish, char)
  integer  cnt
  cnt = 0
  while  start <= finish cycle 
    cnt = cnt + 1 if  byteinteger(start) = char
    start = start + 1
  repeat 
  result  = cnt
end 
endoffile