Q44

In optimal page replacement algorithm, information about all future page references is available to the operating system (OS). A modification of the optimal page replacement algorithm is as follows: The OS correctly predicts only up to next $4$ page references (including the current page) at the time of allocating a frame to a page. A process accesses the pages in the following order of page numbers:

$$1,3,2,4,2,3,1,2,4,3,1,4$$

If the system has three memory frames that are initially empty, the number of page faults that will occur during execution of the process is __________. (Answer in integer)