Summary tables and figures. For validation of final products, several charts and tables are provided in order to display statistical information of trimming results. A: The numbers of reads and bases, and minimum and maximum read lengths for each cleaning step. B: The distribution of read lengths for each cleaning step. C: The distribution of quality scores for each cleaning step. D: The percentage of top 30 k-mers in cleaned sequences. E: The histogram of primer matches. F: The number of good and bad reads in terms of primer combinations. G: The number of primers identified at each base position. H: The histogram of lengths of trimmed poly A tails and T heads.