The 2 specifies the number of threads that synchronize (nthread in sync. c). each thread sits in a tight loop. in each loop iteration, a thread calls synchronizer() and then sleeps for some random number of microseconds. the assert triggers, because one thread leaves the synchronizer before the other thread has reached the synchronizer. the desired behavior is that all threads should block until nthread threads have called synchronizer. your goal is to achieve the desired behavior.

Assume that two parallel arrays have been declared and initialized: healthoption an array of type char that contains letter codes for different healthcare options and annual cost an array of type int. the i-th element of annual cost indicates the annual cost of the i-th element of healthoption. in addition, there is an char variable, best2.write the code necessary to assign to best2 the health option with the lower annual cost, considering only the first two healthcare options. thus, if the values of healthoption are 'b', 'q', 'w', 'z' and the values of annualcost are 8430, 9400, 7050, 6400 your code would assign 'b' to best2 because 8430 is less than 9400 and is associated with 'b' in the parallel array. (we ignore 'w' and 'z' because we are considering only the first two options.)