Internal table checking for initial values in between

Hi Folks,

  I have internal table with 10 fields , i have to first check what are the fields filled with values eg field1 to field 6 they maintain and from field7 to field10 is '0'.if so i have to check from field1 to field6 (what user maintains in excel) is there any zero values maintained if so i have to raise an error message.

how can i check

1. from which field to field the values are maintained.

2. if so is there any intial values maintained in between the maintained field values.

fld1     fld2     fld3     fld4     fld5     fld6     fld7     fld8     fld9     fld10

10     20          0         0     50         70     0          0     0          0

Thanks,

smriti