BEGIN{FS="\t"}{
    m=$8;n=0;
    if (length(m)>0){
	n=split(m,a,",");
    }
    o[n]++;
    r++;
    s+=n;
}END{
    print "nreads "r
    print "nmm "s;
    print "avgmm "1.0*s/r;
    for (n in o){ print n" "o[n]}
 }