Question

Suppose the following operations were performed on an empty stack: push (0): push (9): push (12): push (1) Insert numbers in the following diagram to show what will be stored in the static stack after the operations have executed.

Short answer

Answer: The contents of the stack, from bottom to top, are: 0, 9, 12, 1.

Step-by-step solution

Start with an empty stack

Initialize the stack as empty.

Perform the first push operation

Push 0 into the stack. The stack will now contain: [0]

Perform the second push operation

Push 9 into the stack. The stack will now contain: [0, 9]

Perform the third push operation

Push 12 into the stack. The stack will now contain: [0, 9, 12]

Perform the fourth push operation

Push 1 into the stack. The stack will now contain: [0, 9, 12, 1] After executing all the push operations, the stack will now have the following numbers (from bottom to top): 0, 9, 12, 1.

Key concepts

Push Operation

Understanding the push operation in a stack is fundamental in stack data structure manipulation. In simple terms, the push operation adds an element to the top of the stack. Think of it as stacking books; you always add the next book on top of the previous one.

In the exercise, when the command push(0) is executed, it places the value 0 on top of the stack, which is initially empty. Subsequent push commands add their respective values on top, each becoming the new 'top' of the stack. The process continues with push(9), push(12), and finally push(1) resulting in a stack with these values from top to bottom: 1, 12, 9, 0.

Stack Data Structure

A stack is a collection that follows the Last-In-First-Out (LIFO) principle. This means the last element added is the first one to be removed. Visualize a pile of plates; you can only take the top plate off first without disturbing the others.

Stacks are useful in situations that require reversing items or tracking history, such as browsing history or undo functionality in software. In C++, stacks can be easily implemented using the Standard Template Library (STL) which provides ready-to-use stack data types with essential functions like push() and pop().

Data Manipulation

Data manipulation in programming refers to the process of handling data to achieve a desired output. In the context of stack operations, manipulation involves push (adding data), pop (removing data), and sometimes peek (viewing the top element without removing it).

C++ facilitates this with its powerful features that allow for manipulating data structures like stacks. By using push and pop operations correctly, you can maintain control over the flow of data within your program, ensuring logic consistency in your algorithms and solutions.

C++ Programming

C++ is a widely-used programming language that provides a mix of high-level and low-level capabilities. A feature that stands out is its support for diverse data structures and the operations that govern them, such as the stack operations we've discussed.

Using C++ for stack operations is exemplary due to its efficiency and the control it offers to developers. Beginners who master stack manipulations in C++ have taken an essential step in understanding how data can be managed in programs which is a cornerstone of both simple and complex applications.