bug fix

src/rock.cpp

@@ -128,6 +128,7 @@ void lowFilterCMS(FqBaseBackend* map_id_backend[],int nb_be,int k, CountMinSketc
             unsigned int j=it_offs->first;
             for (it_struct=it_offs->second.begin();it_struct!=it_offs->second.end();it_struct++) {
                 // read dna string corresponding to fastq record
+                if (it_struct->fileid) {
                 DnaSeqStr a_seqs[2];
                 init_DnaSeqStr(&a_seqs[0]);
                 init_DnaSeqStr(&a_seqs[1]);
@@ -137,6 +138,7 @@ void lowFilterCMS(FqBaseBackend* map_id_backend[],int nb_be,int k, CountMinSketc
                 ret=pcms->isBeneathMinKappa(nbrKmerDecompo);
                 if (ret) it_struct->fileid=0;
                 nbrKmerDecompo.clear();
+                }
             }
         }
     }