Formula to count if a text is written in a cell

Question

a	0
a	1
a	2
a	3
a	4

Count starts at 0. ArrayFormula is used and data is checked in a specified range. If a value is written in the cell, it counts. However, if the cell is empty, it does not count. I want to express it in a formula!

Answer 1

Use SCAN, like this:

=ArrayFormula(IF(A1:A10="",,SCAN(-1,A1:A10,LAMBDA(a,c,a+(c<>"")))))