Hi,

I have the following data in the format as shown (note: there are more than 1 blank spaces between each field and the spaces are not uniform, meaning there can be one blank space between field1 and field2 and 3 spaces between field3 and field4, in this example, # are the spaces in between the fields):
________________________________________
num1a###num2a#num3a#####num4a##num5a
num1b###num2b##########num4b#######
#######num2c#num3c#####num4c##num5c
#######num2d#num3d#####num4d##num5d
num1e###num2e#num3e#####num4e##num5e
num1f########################num5f
________________________________________

i need to include ; as the field delimiter and the required output is:
________________________________________
num1a;num2a;num3a;num4a;num5a
num1b;num2b;;num4b;
;num2c;num3c;num4c;num5c
;num2d;num3d;num4d;num5d
num1e;num2e;num3e;num4e;num5e
num1f;;;;num5f
________________________________________

I tried using
sed -e 's/ */;/g'
but it will take consecutive blank fields as one blank field. Can anyone help?