SQL> select * From test;

    AMOUNT F
---------- -
      1000 F
      2000 F
      3000 V
      4000 V
      5000 V

SQL> select decode(flag, 'F', amount, 0) f,
  2         decode(flag, 'V', amount, 0) v
  3  from test;

         F          V
---------- ----------
      1000          0
      2000          0
         0       3000
         0       4000
         0       5000

SQL>