Shell Programming and Scripting

Dear power users,

I have a file like this:

AA 8
AA 6
AA 5
AA 4
AA 3
BB 9
BB 4
BB 3
BB 2
ZZ 5
ZZ 3
ZZ 1
...
The characters in colum one are variously different until the end of the file. I want to extract the maximum value of each entry in column one, so the output will be like this:

AA 8
BB 9
ZZ 5
...

Anybody could help me to made the script, since the file consist of about 10.000 lines? I have search in the rest of the forum, but found no clue. Tx

Code:

sort -t" " -k 1,1 -k2,2r infile| awk 'a != $1 {a=$1; print $0; next}'
AA 8
BB 9
ZZ 5

Ok..Tx very much for the enlightenment :-)

Another approach:

Code:

awk 'a[$2]<$2{a[$2]=$2} END{for(i in a){print i, a[i]}}' file

Regards