I have some files named file1, file2, fille3......etc. These files are in a folder f1. The content of files are shown below. I would like to count the unique pairs of third column in each file. some files have no data. It should be printed as zero. Your help would be appreciated.
file1
ARG ASP 155-122 155 122 B-A NH1-OD1 3.47172
ARG ASP 155-122 155 122 B-A NH1-OD2 3.61227
ARG GLU 155-124 155 124 B-A NH2-OE1 2.97287
ARG GLU 155-124 155 124 B-A NH2-OE2 3.92621
ARG ASP 156-29 156 29 B-A NH1-OD1 3.4752
ARG ASP 156-29 156 29 B-A NH1-OD2 3.18324
ARG GLN 156-125 156 125 B-A NH1-OE1 3.12772
file2
ARG GLN 537-116 537 116 B-A NH2-OE1 3.82477
ARG GLN 537-116 537 116 B-A NH2-OE2 3.82477
Desired output
file1 4
file2 1