20221106c2

1:

semaphore sem(1);
int sum=0;
queue q;

void sumstop(int v):
	if i < 0:
		q.enqueue(v)
		sem.P()
	else
		i--

int sumgo(void):
	for each elem in q:
		int val=q.dequeue()
		sum=sum + val
	return sum

2:

queue values;
semaphore s(0);
int sum=0;

void sumstop(int v):
	s.P()
	values.eqnueue(v)

int sumgo(void):
	while !value.isEmpty():
		s.V()
		mutex.P()
		sum=sum+values.dequeue()
		mutex.v()
	return sum

3:

shared int sum=0;
semaphore wait(0);
semaphore mutex(1);

void sumstop(int v):
	mutex.P();
	sum = sum + v;
	mutex.V();
	wait.P();

int sumgo(void):
	wait.V();
	somma = sum;
	mutex.P()
	sum = 0
	mutex.V()
	return somma;

4:

queue<int> processlist;
semaphore mutex(1);
semaphore s(0);

void sumstop(int v):
	mutex.P();
	processlist.enqueue(v);
	mutex.P();
	S.P();

int sumgo(void):
	int sum = 0;
	mutex.P();
	while processlist.top() != NULL:
		sum += processlist.dequeue();
		S.V();
	mutex.V()
	retutn sum;

5:

int counter = 0;
int sum = 0;
semaphore mutex(1);
semaphore blocked(0);

void sumstop(int v):
  mutex.P();
	sum+=v;
	counter++;
	mutex.V();
	blocked.P();

int sumgo(void):
	  mutex.P();
		intret = sum;
		sum = 0;
		for (int i=0; i<counter; i++)
			blocked.V()
		counter = 0;
		mutex.V()
	return intret

6:

int sum = 0;
mutex = new semaphore(1);
queue q;

void sumstop(int v):
	mutex.P();
	sum += v;
	sintpid = getpid();
	suspend(pid);
	mutex.V();

int sumgo(void):
	mutex.P();
	while !q.empty():
		resume(q.dequeue())
	int value = sum;
	sum = 0;
	return value;

7:

int nP, nV = -1, 0;
int somma = 0
int val[]
semaphore mutex(1);
semaphore s(0);

void sumstop(int v):
	mutex.P()
	val[nP++].add[v]
	s.P()
	np--
	v[0].delete

int sumgo(void):
	mutex.P();
	nV++
	if nP > 0:
		s.V()
		for (int i=0; i<nV; i++)
			somma += val[i]
			nv--
	else
		mutex.V()
	return somma

8:

struct blocked {
	semaphore sem(0);
	int value = 0;
};

semaphore mutex(1);
list<blocked> procs = new list<blocked>();

void sumstop(int v):
  mutex.P()
	blocked bl = new blocked();
	bl.value = v
	procs.add(bl)
	bl.sem.P()
	mutex.V()

int sumgo(void):
  mutex.P();
	int count = 0;
	foreach proc in procs:
		count += proc.value
		procs.remove(proc)
		proc.sem.V()
	mutex.V()
	return count;

9:

semaphore s[] new sem(0)
semaphore s1 new sem(0)
int tot, waiting = 0;

void sumstop(int v):
	waiting++
	s[waiting - 1].P()
	waiting--
	tot = tot + v
	if waiting == 0:
		s1.V()

int sumgo(void):
	if waiting = 0:
		return 0
	for (i = waiting -1; i == 0; i--)
		s[i].V()
	s1.P() // per aspettare che tutti abbiano fatto la somma
	return tot

10:

int nw = 0
int currsum = 0
semaphore mutex(1)
semaphore wait2go(0)

void sumstop(int v):
  mutex.P()
	currsum += v;
	nw++;
	mutex.V()
	wait2go.P()
	if --nw > 0:
		wait2go.V()
	else
		mutex.V()

int sumgo(void):
  mutex.P();
	if mw == 0:
		mutex.V()
		return 0;
	int sum = cursum;
	cursum = 0;
	wait2go.V();
	return sum

11:

semaphore mutex(1);
semaphore semwait(0);
int sum=0;
int wait=0;

void sumstop(int v):
	mutex.P()
	wait++
	sum += v;
	mutex.V()
	semwait.P()
	mutex.P()
	wait--;
	mutex.V()
	if wait > 0:
		semwait.V()

int sumgo(void):
	if wait == 0:
		return 0
	semwait.V();
	while (wait > 0) {}
	int val = sum
	mutex.P()
	sum = 0;
	mutex.V()
	return val;

12:

semaphore mutex(0)
volatile int counter = 0

void sumstop(int v):
	counter = counter + v;
	mutex.P()

int sumgo(void):
	int val = counter;
	while (mutex.value != 0)
		mutex.V()
	counter = 0;
	return counter