Consider a class that uses the following variables to implement an array-based stack:
String [ ] s = new String[100];
Int top = 0;
The boolean method to check for an empty stack can be written as:
A) return top;
B) if (top == 0.
Return true;
Else
Return false;
C) if (s == null.
Return true;
Else
Return false;
D) if
Return true;
Else
Return false;

Question

Quizplus · Accepted Answer

Option B checks if the top variable (which indicates the index of the topmost element in the stack) is equal to zero, i.e., if the stack is empty. If top equals zero, the method returns true, otherwise, it returns false. This is the correct way to check for an empty stack.

Option A just returns the value of top, which isn't a boolean value and doesn't indicate whether the stack is empty.

Option C checks if the array itself is null, but this doesn't necessarily mean that the stack is empty.

Option D is incomplete and doesn't provide any logic to check for an empty stack.

Consider a Class That Uses the Following Variables to Implement