Question

Given an initially empty stack, what would the stack look like after the following operations? Assume the answers show the top of the stack on the left.

push(L)
push(X)
push(R)
push(N)
push(F)

a. O L R F
b. O L X R N E
c. O F N R X L
d. O N R X

Answer 1

After performing the sequence of push operations on an empty stack, the stack will show the Last-In, First-Out (LIFO) order: F at the top, followed by N, R, X, and L at the bottom. The correct answer that represents the stack from top to bottom is therefore 'F N R X L'.

Step-by-step explanation:

The question asks what the stack would look like after a sequence of push operations starting with an initially empty stack. In stack operations, items are added to the top and removed from the top, so the last item added is the first to be removed, following a Last-In, First-Out (LIFO) approach.

To visualize this, let's perform the operations one by one:

• push(L) - Stack now contains: L (top)
• push(X) - Stack now contains: X (top), L
• push(R) - Stack now contains: R (top), X, L
• push(N) - Stack now contains: N (top), R, X, L
• push(F) - Stack now contains: F (top), N, R, X, L

Therefore, after these operations, the stack from top to bottom would be: F, N, R, X, L.

The correct answer is therefore option c, which properly lists the items from the top to the bottom of the stack: O (which we assume is irrelevant and therefore ignore) F N R X L.