use warnings;
use strict;              
use Data::Dumper;        
use Carp;

my @aoa;                 
my @temp;

while (<DATA>) {         
    chomp;               
    if (/^Mtf (\d+) (.*) ([A-Z]+)$/) { # stuck here
        print "$_ \n";            
        push @temp, ($3);
    }
    elsif (/^>(\w+) St (b|f)\d+/) { # not sure how to capture only "f" here
        print "$_\n";             
    }
    push @aoa, [@temp];
}

#print Dumper \@aoa ;