Question

Suppose savings and expenses are variables of type double that have been given values. Write an \(i f\) -else statement that outputs the word Solvent, decreases the value of savings by the value of expenses, and sets the value of expenses to \(0,\) provided that savings is at least as large as expenses. If however, savings is less than expenses, the \(i f\) -else statement simply outputs the word Bankrupt, and does not change the value of any variables.

Short answer

Question: Given the savings and expenses of an individual, implement a program that determines whether they are solvent or bankrupt. If they are solvent, update the amounts of savings and expenses accordingly. Explain how this can be done using an if-else statement in the code. Answer: To determine whether an individual is solvent or bankrupt, we can use an if-else statement to compare their savings and expenses. If the savings value is greater than or equal to the expenses, the individual is considered solvent. In this case, we need to output "Solvent", subtract expenses from savings, and set expenses to 0. If the savings value is less than expenses, the individual is considered bankrupt, and we simply output "Bankrupt", leaving savings and expenses unchanged. The implemented if-else statement would look like the following: ```java if (savings >= expenses) { System.out.println("Solvent"); savings = savings - expenses; expenses = 0; } else { System.out.println("Bankrupt"); } ```

Step-by-step solution

Compare savings and expenses

Based on the condition, we will write an if-else statement to compare the savings and expenses. If the savings value is greater than or equal to the expenses, proceed to Step 2; otherwise, go to Step 3.

Output "Solvent" and update variables

If savings is greater than or equal to expenses, output "Solvent", subtract the value of expenses from savings (savings = savings - expenses), and set expenses to 0.

Output "Bankrupt"

If savings is less than expenses, output "Bankrupt" and don't change the values of savings and expenses. The resultant code will look like this: ``` if (savings >= expenses) { System.out.println("Solvent"); savings = savings - expenses; expenses = 0; } else { System.out.println("Bankrupt"); } ```

Key concepts

Conditional Statements

Conditional statements are a fundamental component in programming, allowing a program to make decisions based on certain conditions. They are at the heart of control flow in programs, wherein the sequence of execution of the code depends on the outcome of these conditions. In C++, if and else are the primary keywords used to construct conditional statements.

In the exercise given, the if-else statement evaluates whether the savings variable is at least as large as the expenses variable. This is a binary decision: if the condition is true, one block of code will run, and if it is false, a different block of code will run. This conditional logic allows for distinct outcomes based on the state of the program's data at the time of evaluation.

It's important for students to understand that conditional statements are not limited to just two outcomes. While the if-else structure processes two paths, you can use else if to extend the logic for multiple conditions. These powerful constructs enable C++ programs to handle complex decision-making processes.

Variable Comparison

Comparing variables is a fundamental operation that precedes most control structures in programming. In the provided exercise, a comparison between two variables of type double—savings and expenses—determines the flow of the program.

To compare variables, C++ offers a set of relational operators like >= (greater than or equal to), < (less than), > (greater than), == (equal to), and so on. When the if statement uses the >= operator, it checks whether the value of savings is greater than or equal to expenses. This comparison yields a boolean result—true or false—which the if-else statement then uses to determine which code block to execute.

Understanding variable comparison is crucial for students, as it forms the basis for many programming tasks, from controlling the program flow to validating user input and making calculations based on dynamic data.

Programming Logic

Programming logic involves the application of reasoning to the design of a sequence of instructions that leads to a desired outcome or behavior of a program. It is a cornerstone of developing functional and efficient code that solves problems and performs tasks.

In the context of the exercise, the programming logic is manifested in determining the financial state based on the comparison between savings and expenses. The logic implemented here is simple yet demonstrates the principle of conditional execution based on variable values. If the financial condition allows (i.e., savings is more than or equal to expenses), adjustments are made to the financial variables; if it does not (i.e., savings is less than expenses), the program simply indicates a state of bankruptcy without altering the values.

Grasping the concepts of programming logic allows students to write coherent code that not only executes correctly but can also be read and understood by other programmers. It is the logical structure that underpins algorithms and determines how tasks are performed and problems are solved in programming. Therefore, developing strong logical thinking skills is essential for budding programmers.