Compare arrays of strings by matching only the specified number of leading characters of the elements, ignoring the case of letters.
a An array of strings.
b An array of strings, of the same size as a .
y An integer array, of the same size as the input, whose elements are 1 if the n leading characters of corresponding elements in the inputs are the same if the cases of letters are ignored, and 0 otherwise.

If one of the inputs is a scalar, it is compared with all the elements of the second array.