What is the effect of the following for Stack s? What would the stack look like?

What is the effect of the given operations on the stack, assuming an initially empty stack?

The effect of the given operations on the stack, assuming an initially empty stack, would be as follows:

  • s.push("www.nsf.gov"): This operation pushes the string "www.nsf.gov" onto the stack. After this operation, the stack would contain one element, which is "www.nsf.gov".
  • s.pop(s.push("smithsonian.org")): Here, the inner operation s.push("smithsonian.org") is executed first. It pushes the string "smithsonian.org" onto the stack. So, after this operation, the stack would contain two elements: "www.nsf.gov" and "smithsonian.org". Next, the outer operation s.pop is executed. It removes the top element from the stack, which is "smithsonian.org". Therefore, after this operation, the stack would contain only one element, which is "www.nsf.gov".
In summary, after performing the given operations, the stack would have the following content: ["www.nsf.gov"]. The "smithsonian.org" string is pushed and then popped, resulting in its removal from the stack.

Explanation:

Stack Operation Explanation:
A stack is a data structure that follows the Last In First Out (LIFO) principle, meaning the last element added to the stack will be the first one removed. Let's analyze the given operations on the stack:

1. s.push("www.nsf.gov"):

When the operation s.push("www.nsf.gov") is performed on an initially empty stack, the string "www.nsf.gov" is added to the stack. As a result, the stack now contains one element, which is "www.nsf.gov".

2. s.pop(s.push("smithsonian.org")):

This operation consists of two steps. First, the inner operation s.push("smithsonian.org") pushes the string "smithsonian.org" onto the stack. So, after this step, the stack contains two elements: "www.nsf.gov" (added earlier) and "smithsonian.org" (added now).
Next, the outer operation s.pop is performed. This operation removes the top element of the stack, which is "smithsonian.org" in this case. Therefore, after this step, the stack only contains the element "www.nsf.gov".

In conclusion, the given operations result in the stack having only the element "www.nsf.gov" after the complete execution. The string "smithsonian.org" was added to the stack and then removed by the pop operation.

This demonstrates the basic concept of stack operations and how elements are added and removed in a Last In First Out manner. Understanding such operations is essential in programming and data structure implementation.
← Worksheet management in spreadsheet programs a reflective discussion Building a personal check program in java →