Answer:
Explanation:
Following are the Semaphores:
Customers: Counts waiting customers;
Barbers: Number of idle barbers (0 or 1)
mutex: Used for mutual exclusion.
Cutting: Ensures that the barber won’t cut another customer’s hair before the previous customer leaves
Shared data variable:
count_cust: Counts waiting customers. ------------copy of customers. As value of semaphores can’t access directly.
// shared data
semaphore customers = 0; semaphore barbers = 0; semaphore cutting = 0; semaphore mutex = 1;
int count_cust= 0;
void barber() {
while(true) { //shop is always open
wait(customers); //sleep when there are no waiting customers
wait(mutex); //mutex for accessing customers1
count_cust= count_cust-1; //customer left
signal(barbers);
signal(mutex);
cut_hair();
}
}
void customer() {
wait(mutex); //mutex for accessing count_cust
if (count_cust< n) {
count_cust= count_cust+1; //new customer
signal(customers); signal(mutex);
wait(barbers); //wait for available barbers get_haircut();
}
else { //do nothing (leave) when all chairs are used. signal(mutex);
}
}
cut_hair(){ waiting(cutting);
}
get_haircut(){
get hair cut for some time; signal(cutting);
}
Answer:
c. both the user and the provider of encrypted data.
Explanation:
In assymetric key encryption, you will need the public key of the sender to decode the information along with your private key to decode the encrypted information. if you don't have any of the keys, you won't be able to read the information. You must have both in order to read the information sent.
Answer:
computer means a technology or digitalized form of technology which makes student life better by giving solution to the problem and promote creativenes.
Google is famously known as a search engine and it is being used around the globe. Aside from being a search engine, it also offers other services such as productivity software or google docs, e-mail services like Gmail, cloud storage or the google drive and it also offers social networking services through google plus. Google also has some desktop application for free of use such as google chrome, picasa and instant messaging like hangouts. Their mission statement as for being the most used search engine is "to organize the world's information and make it universally accessible and useful".
