Consider the following program segments for two different processes (P1, P2) executing concurrently and where a and b are not shared variables, but x starts at zero and is a shared variable
Processor #1 Processor #2
for (a = 1; a <= 3; a++) for (b = 1; b <= 3; b++)
x = x + 1; x = x + 1;
If P1 and P2 execute only once and concurrently, then the final minimum possible value of x is ____