IntLength determines the number of digits in a base 10 integer.

IntsLength determines the number of digits in a list of base 10 integers, accounting for separators between each integer.

WriteInteger writes a base 10 integer to a buffer at a given index.

WriteIntegers writes a slice of base 10 integer to a buffer at a given index, separating each value with the given separator, returning the index at which the write ends.