MGY441 · Alignment lab
Fill the edit-distance matrix one cell at a time. Every cell is the cheapest way to turn one prefix into the other — the smaller of a substitution (diagonal), or a gap (from the left or from above). Get one wrong and we'll show you exactly how it's built.
How a cell is built
The first row and column are filled in for you — they're just gaps piling up (0, 1 gap, 2 gaps, …). Click any interior cell and type its value: the min of three moves — come diagonally and pay for a match/mismatch, or come from the left or from above and pay one gap.