Question

A retail store grants its customers a maximum amount of credit. Each customer's available credit is his or her maximum amount of credit minus the amount of credit used. Write a pseudocode algorithm for a program that asks for a customer's maximum credit and amount of credit used, then calculates and displays the customer's available credit.

Short answer

Answer: To calculate the available credit for a customer, subtract the credit used from the maximum credit (available_credit = max_credit - credit_used).

Step-by-step solution

Ask for the customer's maximum credit

First, we need to ask the customer for their maximum amount of credit. The input should be stored in a variable, let's call it max_credit.

Ask for the customer's amount of credit used

Next, we need to ask the customer for the amount of credit they have used so far. This input should be stored in another variable, let's call it credit_used.

Calculate the available credit

Now that we have the maximum credit and the credit used, we can calculate the available credit. To do this, subtract the credit used from the maximum credit: available_credit = max_credit - credit_used.

Display the available credit

Finally, we need to display the customer's available credit. To do this, simply output the available_credit variable. The pseudocode algorithm should look like this: 1. Ask for max_credit 2. Ask for credit_used 3. available_credit = max_credit - credit_used 4. Display available_credit

Key concepts

Algorithm Design

Algorithm design is the process of creating a step-by-step sequence to solve a problem or perform a task. In the context of programming, it involves drafting out instructions in a logical order that can later be converted into code. In our case, the algorithm is intended to calculate the available credit for a customer at a retail store.

When designing an algorithm, it is essential to:

• Clearly define the problem you are solving. Here, the problem is finding out how much credit a customer has left after using part of their maximum credit.
• Determine the steps involved. For our retail store problem, we outline the steps to ask for input, perform a calculation, and show the result.
• Ensure the sequence of steps is logical and efficient. Each input is received before any calculations are made, ensuring accurate and reliable output.

Pseudocode is often used in algorithm design as it allows developers to outline their thoughts in a human-readable format that resembles programming languages but is not bound by their strict syntax.

Variables

Variables are fundamental components of programming that store information to be used later in the code. They act as containers for data values. In our pseudocode example, we use variables to capture and handle user input for calculations.

• max_credit: This variable stores the customer's maximum credit amount, which is the total limit available before any spending or borrowing has been done.
• credit_used: This variable keeps track of the amount of credit that has already been consumed by the customer, ensuring that we know how much has been deducted from the total limit.
• available_credit: This is the result of the calculation and holds the remaining credit available to the customer after subtracting the credit used from the maximum credit.

Choosing meaningful variable names, like those above, helps in making the code more understandable and maintainable, as anyone reading the code can quickly grasp what each variable represents.

Input/Output in Programming

Input and output (I/O) operations are essential in programming as they allow interaction between the user and the system. These operations are particularly important for programs that require user input to generate results.

In our pseudocode algorithm, input operations are used to:

• Request the customer's maximum credit. This is an initial input collected to understand the upper limit of the customer's line of credit.
• Ask for the amount of credit already used. Gathering this input is necessary to calculate how much is left.

Once the required calculations are completed, an output operation displays the result, the remaining available credit, directly to the customer.

Properly handling input and output is crucial as it ensures data is correctly captured and results are clearly communicated. It also contributes to a smoother user experience, as users receive prompt and accurate feedback from the system.