Question Discussion & Solution

Process    
P0            
P1                             
P2                             
 
Maximum needs (process-wise: P0 through P2 top to bottom)    
10             
4   
9
 
Currently allocated (process-wise)
5
2
2

Method used by P1 :
while(S1==S2);
Critical section
S1 = S2;
 
Method used by P2 :
while(S1!=S2);
Critical section
S2 = not(S1);