The function func is executed simultaneously by $3$ threads. What is the value of final at the end?$($Lock$($ob$)$ acquires a mutual exclusion lock, and Unlock$($obj$)$ releases the lock.$)$Lock$*$ obj:int func$($void$)($int final $=0,$if $($final$==0)($final#t$,$Unlock$($ob$])$:return final;