repeat
   s$ = input
   until s$ = ""
   a = strpos s$ "a"
   b = strpos s$ "b"
   c = strpos s$ "c"
   if a > 0 and b > a and c > b
      print s$
   .
.
# 
# the content of unixdict.txt 
input_data
10th
drawback
fabric
