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Answer the questions on the class described below.
A class CustomerService is defined to resolve customer service requests in the order in which they…
A class CustomerService is defined to resolve customer service requests in the order in which they are received.
The details of the members of the class are given below:
| Class name | : | CustomerService |
|---|---|---|
| Data members/instance variables: | ||
| services[ ] | : | array to store customer service request |
| size | : | to store the maximum capacity of the array |
| first | : | to store the index of the first customer service request |
| last | : | to store the index of the last customer service request |
| Methods/Member functions: | ||
| CustomerService(int s) | : | constructor to assign size = s, first = 0 and last = 0 |
| void add(int reqst) | : | to insert a request at index last, if space is available, otherwise display “Request cannot be accepted at the moment” |
| int del( ) | : | to remove and return the request at index first, if any, else return -9999 |
(i)[4.0]
Specify the class CustomerService giving details of the functions void add(int) and int del( ). Assume that the other functions have been defined.
(ii)[1.0]
Name the entity described above and state its principle.
Answer
Answer (i)
AIvoid add(int reqst)
{
if (last == size)
System.out.println("Request cannot be accepted at the moment");
else
{
services[last] = reqst;
last++;
}
}
int del()
{
if (first == last)
return -9999;
else
{
int val = services[first];
first++;
return val;
}
}Answer (ii)
AIEntity: Queue
Principle: FIFO (First In First Out) — the request that is added (inserted) first is the first one to be removed and serviced.
From ISC 2026 Improvement Computer Science Paper 1, question 9.