Print two matched words from the same line

Hi experts

I need to pick 2 matched words from the same line.....
I have given below an example file

eg:

O14757 hsa04110 hsa04115 2 P38398 hsa04120 1 
O15111 hsa04010 hsa04210 hsa04920 hsa04620 hsa04660 hsa04662 hsa05200 hsa05212 hsa05221 hsa05220 hsa05215 hsa05222 hsa05120 13 O14920 hsa04010 hsa04210 hsa04910 hsa04920 hsa04620 hsa04660 hsa04662 hsa05200 hsa05212 hsa05221 hsa05220 hsa05215 hsa05222 hsa04930 hsa05120 15 
O15264 hsa04010 hsa04370 hsa04912 hsa04620 hsa04664 hsa04670 hsa05014 hsa05120 8 Q15139 
O15297 hsa04115 1 Q00987 hsa04120 hsa04110 hsa04115 hsa05200 hsa05214 hsa05220 hsa05218 hsa05219 hsa05215 9 
O43464 hsa05012 1 P98170 hsa04120 hsa04210 hsa04510 hsa05200 hsa05222 5 

From the above file i have to pick only the 6 letter alphanumerical words(highlighted words) in the given below format

ie,

 O14757    P38398 
 O15111    O14920 

Pls reply me asap

Assuming that the number of spaces between the matches in the line don't matter:

perl -lne '@a=(/([A-Z0-9]{6})/g); print "@a"' test.txt
O14757 P38398
O15111 O14920
O15264 Q15139
O15297 Q00987
O43464 P98170

Hi,

Try this

#!/usr/bin/perl

while (<>) {
        chomp ;
        @array = split;
        for (@array) {
        print "$_\t" if (length($_) == 6);
        }
        print "\n";
}
grep -o '[A-Z][0-9]\{5\}' infile|xargs -n2
O14757 P38398
O15111 O14920
O15264 Q15139
O15297 Q00987
O43464 P98170
while(<DATA>){
	my @tmp = split;
	print join " ", grep {length($_) eq 6} @tmp;
	print "\n";
}
__DATA__
O14757 hsa04110 hsa04115 2 P38398 hsa04120 1 
O15111 hsa04010 hsa04210 hsa04920 hsa04620 hsa04660 hsa04662 hsa05200 hsa05212 hsa05221 hsa05220 hsa05215 hsa05222 hsa05120 13 O14920 hsa04010 hsa04210 hsa04910 hsa04920 hsa04620 hsa04660 hsa04662 hsa05200 hsa05212 hsa05221 hsa05220 hsa05215 hsa05222 hsa04930 hsa05120 15 
O15264 hsa04010 hsa04370 hsa04912 hsa04620 hsa04664 hsa04670 hsa05014 hsa05120 8 Q15139 
O15297 hsa04115 1 Q00987 hsa04120 hsa04110 hsa04115 hsa05200 hsa05214 hsa05220 hsa05218 hsa05219 hsa05215 9 
O43464 hsa05012 1 P98170 hsa04120 hsa04210 hsa04510 hsa05200 hsa05222 5