I have an array and I want to know how many indexing values are needed for the value of the array to increase or decrease

I have an array and I want to know how many indexing values are needed for the value of the array to increase or decrease for example a unit or more. For example, a=[1 1 1 3 3 3 3 2 2 2] and the indexing values would be 4 and 8.

[Stephen23]

duplicate:

https://www.mathworks.com/matlabcentral/answers/390078-i-have-an-array-and-i-want-to-know-how-many-indexing-values-are-needed-for-the-value-of-the-array-to