A process executes the code
fork $$\left( {\,\,\,} \right);$$
fork $$\left( {\,\,\,} \right);$$
fork $$\left( {\,\,\,} \right);$$
The total number of child processes created is

Consider the $$3$$ processes, $$P1,$$ $$P2$$ and $$P3$$ shown in the table.

Process	Arrival Time	Time Units Required
P1	0	5
P2	1	7
P3	3	4

The completion order of the $$3$$ processes under the policies $$FCFS$$ and $$RR2$$ (round robin scheduling with $$CPU$$ quantum of $$2$$ time units) are

Fetch_And_Add (X, i) is an atomic Read-Modify-Write instruction that reads the value of memory location X, increments it by the value i, and returns the old value of X. It is used in the pseudocode shown below to implement a busy-wait lock. L is an unsigned integer shared variable initialized to 0. The value of 0 corresponds to lock being available, while any non-zero value corresponds to the lock being not available.

AcquireLock(L){ 
  While (Fetch_And_Add(L,1)) 
  L = 1; 
} 
Release Lock(L){ 
  L = 0; 
}

This implementation

Consider the following C code segment.

int a, b, c = 0;
void prtFun(void);
main( )
{ 
   static int a = 1; /* Line 1 */
   prtFun();
   a + = 1;
   prtFun();
   printf("\n %d %d ", a, b);
}
void prtFun(void)
{ 
   static int a=2;   /* Line 2 */
   int b=1;
   a+ = ++b;
   printf("\n %d %d ", a, b);
}

What output will be generated by the given code segment?