Computer Programming Contest Preparation

    1 123 456 is illegal.
    2 2.2.2. is illegal.
    3 .2 is illegal.
    4 . is illegal.
    5 2.e1 is illegal.
    6 1e+2.2 is illegal.
    7 -e3 is illegal.
    8  is illegal.
    9  is illegal.
   10 1.2 is legal.
   11 1. is illegal.
   12 1.0e-55 is legal.
   13 e-12 is illegal.
   14 6.5E is illegal.
   15 1e-12 is legal.
   16 +4.1234567890E-99999 is legal.
   17 7.6e+12.5 is illegal.
   18 99 is illegal.