Question

If function showValue has the following header: void showValue(int quantity) you would use the statement _________ to call it with the argument 5.

Short answer

Answer: showValue(5);

Step-by-step solution

Identify the function and its arguments

In this case, the function named "showValue" takes a single integer argument, "quantity".

Prepare the function call statement

To call the function with the given argument, we need to write the function name followed by its arguments inside parentheses.

Insert the desired argument value

The exercise asks us to call the function with an argument of 5. So, we will replace "quantity" with 5, resulting in the correct function call.

The final function call statement

The final statement to call the function "showValue" with an argument of 5 is: showValue(5);

Key concepts

Function Arguments

Function arguments in C++ are the values or variables that we pass to a function when we call it. They are important because they allow us to provide input data to functions so that the functions can perform tasks using that data. For instance, consider a function that adds two numbers. The two numbers would be the function's arguments.

When defining a function in C++, we specify the type and name of each argument. This information forms part of the function's 'signature' or 'prototype' as seen in the exercise with the function header void showValue(int quantity). The type int tells us that the argument quantity should be an integer.

In the step by step solution provided, the argument '5' is passed to showValue. The correct way to call showValue with the argument '5' is by writing showValue(5) in the C++ program. This will execute whatever code is defined within the showValue function using '5' as the input for the parameter quantity.

Programming in C++

Programming in C++ involves understanding the syntax and structure of the C++ language, which is rooted in an object-oriented paradigm. As we saw in the example problem, effective communication with a C++ program entails calling functions with the appropriate arguments. In practice, this could mean controlling the flow of the program, manipulating data, or performing calculations.

It is also essential to understand different data types, control structures (like loops and conditionals), libraries, and how to structure code into functions, classes, and files. Error handling and debugging are other critical aspects of C++ programming that ensure the program behaves as expected. As beginners improve their programming skills in C++, they learn to write more efficient and robust code which, in turn, leads to the creation of complex and reliable applications.

C++ Functions

C++ functions are blocks of code that perform a specific task and can be reused throughout a program. Declaring a function involves giving it a return type, a name, and parameters if it takes any input. For example, the return type void in the function showValue means that this function will not return any value after it is executed.

Functions encapsulate logic that can be called from various places within a program, helping to keep code organized and reducing repetition. Defining what the function does only once and then calling it as needed makes a program cleaner and easier to understand. It's important to call a function with the correct number and type of arguments that match its definition, like using the statement showValue(5) to pass '5' to the showValue function as shown in the original exercise.