Eulerian walk and DNA sequence assembly

Children like jigsaw puzzles, and the way to assemble the puzzle is by putting together pieces that match, one by one, till the puzzle is complete. DNA sequence assembly could be thought of as something similar: when a strand of DNA is passed into a particular “sequencing machine”, it gives a large number of short reads of the DNA sequence. This type of technology is called shotgun sequencing. These reads form the jigsaw pieces in the puzzle and one must put together these pieces in an intelligent way to obtain the original sequence. There is, however, a catch here; apriori, we do not know what the original sequence or the“jigsaw big picture” looks like. Yet, the philosophy remains the same: to connect pieces or reads which are similar and hope that the “big picture” is reconstructed