Problem 1290. A different counting method

Given an array (x) of integers, the "counting" array (y) is showing the number of identical consecutive integers in x in front of the integer itself. For example, if

• x = 1
• y = [1 1],

because there is one "1". If then

• x = [1 1]
• y = [2 1],

because there are now two "1"s. Finally, a more complex example:

• x = [1 2 2 4 4 3 0 0 1]
• y = [1 1 2 2 2 4 1 3 2 0 1 1].

So y gets two elements for each series of identical integers in x. (I hope this problem does not exist already)