Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 4: Problem 2

Write four different \(C++\) statements that each add 1 to integer variable \(x.\)

Short Answer

Expert verified
x++; or ++x; or x += 1; or x = x + 1;

Step by step solution

01

Statement Using Postfix Increment Operator

Use the postfix increment operator to increase the value of the variable by 1. In code: x++;. This statement adds 1 to x and then yields the original value of x.
02

Statement Using Prefix Increment Operator

Use the prefix increment operator to increase the value of the variable by 1 before its value is used in expressions. In code: ++x;. This statement increases x by 1 and immediately yields the new value.
03

Statement Using Addition Assignment Operator

Use the addition assignment operator to add a value to the variable. In code: x += 1;. This adds 1 directly to the current value of x.
04

Statement Using Basic Addition

Perform a basic addition to add 1 to the variable and update its value. In code: x = x + 1;. This takes the current value of x, adds 1, and then assigns the result back to x.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Postfix Increment Operator
Understanding the postfix increment operator is essential when learning C++. This operator, represented by two plus signs following a variable, as in x++, is used to increase the value of the variable by 1 after its current value has been used. Imagine you're counting apples in a basket, and after counting each apple, you mark it; this is similar to how the postfix operator works—you use the apple (variable), then mark it (increment).

Here's how you might see it in action:
  • int x = 5;
  • int y = x++;
  • // Now, x is 6 and y is 5

The key point to remember is that the original value of x is used in any expressions or assignments before x itself is incremented.
Prefix Increment Operator
The prefix increment operator is another way to add 1 to a variable in C++. Unlike the postfix version, the prefix increment operator, denoted with two plus signs before a variable, as in ++x, increments the variable's value before it's used anywhere else. It's like preparing all of your apples by washing them before putting them into the basket.

Consider this example:
  • int x = 5;
  • int y = ++x;
  • // x is now 6, and y is also 6

This behavior has implications when the increment is part of a larger expression. It ensures that you're working with the updated value right away.
Addition Assignment Operator
If you're looking to increase a variable's value directly and concisely, the addition assignment operator += is your tool of choice. This operator combines addition and assignment in one sleek motion. For example, the statement x += 1 essentially tells the computer, 'Take the current value of x, add 1 to it, and then make this new sum the value of x.'

It's like saying, 'I have these many apples, I'm getting one more, and that's my new total.' This operator simplifies code and eliminates the need to write the variable out twice, as compared to x = x + 1.
Basic Addition in C++
The most straightforward way to increase a value in C++ is with basic addition. To add 1 to a variable, you simply take its current value, add 1, and then update the variable with the new value using the equals operator. In code, this looks like x = x + 1.

This is equivalent to a one-step process where you hold a certain number of apples, say 'I have one more,' and count them together to find your new total. While this approach is clear and intuitive, especially for those new to programming, it's often substituted with the more concise increment operators or the addition assignment operator in practice.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

\(4.26 \quad\) forward. For example, each of the following five-digit integers is a palindrome: 12321,55555 45554 and \(11611 .\) Write a program that reads in a five-digit integer and determines whether it's a palindrome. [Hint: Use the division and modulus operators to separate the number into its individual digits.

(Checkerboard Pattern of Asterisks) Write a program that displays the following checkerboard pattern. Your program must use only three output statements, one of each of the following forms: cout << "* "; cout << ' '; cout << endl;

Write single \(\mathrm{C}_{++}\) statements or portions of statements that do the following: a) Input integer variable \(x\) with \(\operatorname{cin}\) and \(>>\) b) Input integer variable \(y\) with \(\operatorname{cin}\) and \(>>\) c) Set integer variable i to 1 d) Set integer variable power to 1 e) Multiply variable power by \(x\) and assign the result to power. \(f\) ) Preincrement variable i by 1 g) Determine whether i is less than or equal to y. h) Output integer variable power with cout and \(<<\)

(Dangling-else Problem) State the output for each of the following when \(x\) is 9 and \(y\) is 11 and when \(x\) is 11 and \(y\) is \(9 .\) The compiler ignores the indentation in a \(C++\) program. The \(C++\) compiler always associates an else with the previous if unless told to do otherwise by the placement of braces \\{\\}\(.\) On first glance, you may not be sure which if and else match, so this is referred to as the "dangling-else" problem. We eliminated the indentation from the following code to make the problem more challenging. [Hint: Apply indentation conventions you've learned.] (Dangling-else Problem) State the output for each of the following when \(x\) is 9 and \(y\) is 11 and when \(x\) is 11 and \(y\) is \(9 .\) The compiler ignores the indentation in a \(C++\) program. The \(C++\) compiler always associates an else with the previous if unless told to do otherwise by the placement of braces \\{\\}\(.\) On first glance, you may not be sure which if and else match, so this is referred to as the "dangling-else" problem. We eliminated the indentation from the following code to make the problem more challenging. [Hint: Apply indentation conventions you've learned.]

(Sides of a Triangle) Write a program that reads three nonzero double values and determines and prints whether they could represent the sides of a triangle.
See all solutions

Recommended explanations on Computer Science Textbooks

Big Data

Read Explanation

Computer Network

Read Explanation

Theory of Computation

Read Explanation

Issues in Computer Science

Read Explanation

Problem Solving Techniques

Read Explanation

Computer Organisation and Architecture

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free