Fig. 2.

Illustration of the forward and backward search to correct sequencing errors. The forward search starts from the first k-mer to the last k-mer. At each step the last base of the k-mer is substituted by its alternatives to check the solidity. Inversely, the backward search starts from the last k-mer to the first k-mer. On the contrary to the forward search, the first base of the k-mers are altered other than the last one