Replace a blank cell in a column by a specific text using a macro

Hi All,

INPUT IN EXCEL : ACCOUNTNO BANKNAME DATE ID

123456 SBI 2015-09-08 ADR345
VBI 2014-09-07
BY CASH UBI 2013-09-08 8U8U8


OUTPUT REQUIRED: ACCOUNTNO BANKNAME DATE ID
123456 STATE BANK OF INDIA 08/09/2015 M
BY TRANSFER VIJAYA BANK OF INDIA 07/09/2014 M
BY CASH UNION BANK OF INDIA 08/09/2013 M

ACCOUNTNO COLUMN:HERE WHEN THERE IS A BLANK ,IT SHOULD BE REPLACED WITH BY TRANSFER

BANKNAME COLUMN :WHEN THE INPUT IS IN SHORT FORM,IT SHOULD BE WRIITEN IN FULL FORM.

DATE COLUMN : THE REQUIRED FORMAT IS DD/MM/YYYY

ID COLUMN : THE TOTAL DATA SHOULD BE REPLACED WITH M

I NEED A MACRO TO REARRANGE DATA IN REQUIRED MANNER`