How to delete ending/trailing spaces using awk,sed,perl?

Shell Programming and Scripting
1

How to delete ending/trailing spaces using awk,sed,perl?
Input:(each line has extra spaces at the end)

3456 565     
3 7       
35 878

Expected output:

3456 565
3 7 
35 878
2 
sed 's/ *$//'
3

Can anyone post command for awk and perl?

4

awk:

$ awk 'sub(/ *$/, "", $0)' inputfile

# or simply (although it removes all unnecessary whitespace)...
$ awk '$1=$1' inputfile
5

Perl:

perl -pe 's/ +$//' file
6 
awk 'sub(/ *$/, "")' inputfile