Question

Write the definition of a void function that takes as input two decimal numbers. If the first number is nonzero, it outputs second number divided by the first number; otherwise, it outputs a message indicating that the second number cannot be divided by the first number because the first number is 0

Short answer

Define a function that checks if the first number is zero before dividing the second by it.

Step-by-step solution

Define the Function Header

The function should be named clearly to reflect its purpose. We'll call it `divideIfNonZero()`. This function will take two parameters, which will represent the two decimal numbers.

Check if the First Number is Zero

Inside the function, use an `if` statement to check whether the first number (let's call it `firstNum`) is zero. This condition will determine the output.

Perform Division if First Number is Non-Zero

If the `firstNum` is not zero, proceed to divide the second number (let's call it `secondNum`) by `firstNum`. Use the division operator (`/`) to perform the division and print the result.

Handle Division by Zero Case

In the `else` branch of the `if` statement, output a message indicating that the division cannot be performed because the first number is zero. Use a print statement to display this message.

Key concepts

Void Function

In C++, a void function is a type of function that does not return any value. It is primarily used when you want to perform a series of actions or calculations without needing to get anything back from the function. Unlike other functions that have a return type (like int, float, etc.), a void function simply executes its code and exits.
For instance, in the definition of `divideIfNonZero()` from the exercise, the function's purpose is to take inputs, perform a calculation, and display the results directly, rather than to return a value for further processing. This is ideal for cases where you only need to execute a task without needing the result to be manipulated or stored elsewhere in the program.
Avoiding any return value makes void functions straightforward, as they reduce the complexity of tracking a returned data type. Here are some typical characteristics of void functions:

• No return statement is needed.
• Used when the goal is to execute actions like outputting results.
• Often used for logging, outputting to screen, or modifying external variables.

This approach simplifies the structure of the function, making it easy to understand and inherently suited to tasks like the one in our exercise.

Conditional Statements

Conditional statements in C++ are crucial for making decisions within code. They allow programs to execute different segments of code based on certain conditions. In our exercise, conditional statements are used to determine whether to proceed with division or to handle a zero scenario.
The if-else statement is a common conditional structure and can be explained as follows:

• The `if` portion evaluates a condition. If the condition is true, the code block inside `if` is executed.
• If the condition is false, control passes to the `else` block, if present, executing an alternative code block.

In our example, `if (firstNum != 0)` checks if the first decimal number isn't zero. If it's not zero, the code proceeds with the division.
This logical branch ensures that the program can handle different situations effectively. By using conditional statements, programs become efficient and resilient, able to adapt to varying inputs at runtime.

Division by Zero

Division by zero is a common mathematical error that occurs when you try to divide a number by zero. This operation is undefined because there is no sensible way to distribute a quantity into zero parts. In programming, attempting such a division often leads to runtime errors, which can crash applications if not handled properly.
In our function example, the potential for division by zero is managed by using a conditional statement. By checking the denominator (`firstNum`) before performing the division, we ensure that this error is avoided. If `firstNum` is zero, the function does not attempt the division but outputs a warning message instead.
This approach not only prevents errors but also improves program robustness, ensuring that functions handle all inputs gracefully. Preventing division by zero involves a few best practices:

• Always check the divisor before division.
• Use conditional statements to manage scenarios where division might fail.
• Provide user-friendly feedback when an operation can't be completed.

By following these guidelines, your programs stay stable and users receive clear information, avoiding confusion or a poor user experience.