Given the following program in which two threads concurrently update one

crtical resounce shared data without using lock$($s$).$ Theoretically, how many

different final values may shared data have? Please explain how each different.

value is attained by giving the running order of the statements $($e$\mathrm{.}9.,11$:$9,11$:$10,$

t$1$:$11,2$:$9,12$:$10,$ etc.$)$ of the two threads.