Question

Mark the following statements as true or false. a. \(A\) double type is an example of a simple data type. b. \(\mathrm{A}\) one-dimensional array is an example of a structured data type. c. Arrays can be passed as parameters to a function either by value or by reference. d. A function can return a value of type array. e. The size of an array is determined at compile time. f. The only aggregate operations allowable on int arrays are the increment and decrement operations. g. Given the declaration: int 1 ist [10]; the statement: 1 ist \([5]=1\) ist \([3]+1\) ist [2]; updates the content of the fifth component of the array list. h. If an array index goes out of bounds, the program always terminates in an error. i. In \(\mathrm{C}++,\) some aggregate operations are allowed for strings. ¡. The declaration: char name[16] = "John K. Miller"; declares name to be an array of 15 characters because the string "John K. Miller" has only 14 characters. k. The declaration: char str = "Sunny Day"; declares str to be a string of an unspecified length. I. As parameters, two-dimensional arrays are passed either by value or by reference.

Short answer

a: True, b: True, c: False, d: False, e: True, f: False, g: True, h: False, i: True, j: False, k: False, l: False.

Step-by-step solution

Analysis of statement a

The data type `double` in programming languages such as C++ is a fundamental data type used to represent floating-point numbers. It is not a structured type because it does not store multiple elements but a single numeric value. Therefore, statement a is true: A `double` type is an example of a simple data type.

Analysis of statement b

A one-dimensional array can store multiple elements of the same data type, indexed in a single linear dimension. This makes it a structured data type because it organizes data into configurations other than individual simple values. Thus, statement b is true: A one-dimensional array is a structured data type.

Analysis of statement c

In general programming practice, arrays are always passed by reference because they can be large in size, and copying them entirely could be inefficient. Therefore, statement c is false: Arrays can only be passed by reference to a function, not by value.

Analysis of statement d

Most programming languages, including C++, do not allow functions to return arrays directly. Instead, they may return a pointer pointing to the array or use structures or objects for returning arrays. Thus, statement d is false: A function cannot return a value of type array.

Analysis of statement e

In compiled languages like C++, the size of an array is typically determined at compile time. This is because arrays must allocate memory of a fixed size during compilation to reference these memory locations later. Hence, statement e is true: The size of an array is determined at compile time.

Analysis of statement f

In C++, aggregate operations like copy and assignment are applicable for operations with arrays of integers. Increment and decrement operations usually apply to the elements themselves rather than the whole array. Thus, statement f is false: Increment and decrement operations are not the only operations allowed on int arrays.

Analysis of statement g

The statement attempts to update the sixth element of the array `list` since indexing starts from 0. The content of `list[5]` is updated to `list[3] + list[2]`. Thus, statement g is true: This correctly updates the content of the sixth component of the array.

Analysis of statement h

In many programming languages, accessing an array out of its bounds can lead to undefined behavior, which might not necessarily terminate the program. Thus, statement h is false: The program does not always terminate in an error if an array index goes out of bounds.

Analysis of statement i

In C++, strings have more functionality than simple arrays, allowing for operations like concatenation and comparison. Thus, statement i is true: Some aggregate operations are allowed for strings in C++.

Analysis of statement j

The array `name` is declared to store a string of "John K. Miller" and a terminating null character, requiring 15 elements in total. Thus, statement j is false: `name` is declared as an array of 16 characters to allow for space for the null character.

Analysis of statement k

The declaration is incorrect because the `char` type is intended for single characters, not strings. Instead, a string literal should be stored in a character array or a string object. Thus, statement k is false: The declaration `char str` is incorrect for the purpose of storing a string.

Analysis of statement l

Two-dimensional arrays, similar to one-dimensional arrays, are passed exclusively by reference because of potentially large data size. Thus, statement l is false: They cannot be passed by value, only by reference.

Key concepts

Simple Data Types

In C++, simple data types are those that store a single value at a time. They include basic forms such as integers, floating-point numbers, and characters. These types are straightforward to use and require minimal space in memory.

Here are some examples of simple data types in C++:

• int: Used for storing whole numbers without any decimal points. It can store both positive and negative numbers.
• double: This is used for storing floating-point numbers, which are numbers with decimal points. It's more precise than float and commonly used in calculations that need a higher degree of accuracy.
• char: Used for storing single characters, such as a letter or number enclosed in single quotes. It can represent alphabets, numerical digits, or special characters.

These data types are essential building blocks for more complex data handling and are used in nearly every C++ program to handle basic information.

Structured Data Types

While simple data types hold a single value, structured data types can store multiple related values under a single name. This provides a way to organize complex information efficiently.

One common structured data type is the array. In C++, an array can hold a collection of items of the same data type, indexed by integers.

• One-dimensional arrays are akin to a simple list of elements. They are useful for storing sequences of information, such as a series of numbers or a list of names.
• Two-dimensional arrays can be imagined as tables or matrices, ideal for more complex data like grids of values.

Structured data types are invaluable for organizing data that is naturally related, making it easier to access and manipulate multiple values systematically.

Array Operations

Arrays are versatile data structures, and there are several operations you can perform on them. However, there are some restrictions, particularly in C++.

Here are some basic operations that can be carried out on arrays:

• Accessing Elements: Each element in an array can be accessed using its index. Indexing starts at 0 in C++, so the first element is at index 0.
• Updating Elements: You can change the value of an individual element by specifying its index and assigning a new value.
• Iterating Over an Array: You can loop through an array to perform operations on each element, such as printing each value or summing the elements.

Arrays in C++ are fixed in size, which means their capacity is established at compile time and cannot change at runtime. Also, be cautious with out-of-bounds access, as it can lead to unexpected behavior or program errors.

Function Parameters in C++

In C++, functions can accept parameters to work with external values. Understanding how these parameters are passed is crucial, particularly concerning arrays.

There are generally two ways to pass arguments to a function:

• By Value: This method passes a copy of the argument's value into the function. Changes made within the function do not affect the original variable.
• By Reference: In this approach, a reference to the actual variable is passed, allowing the function to modify the original variable's value.

When it comes to arrays, C++ inherently passes them by reference. This is because copying large arrays could be inefficient. Therefore, functions can alter the contents of an array, impacting the original data set.

However, C++ does not allow arrays to be returned directly from functions. Instead, you can return pointers, or use structures to encapsulate the array if needed.