Arithmetic Shortcuts

Part of the Fundamentals section of Coddy's Java journey — lesson 19 of 73.

Java created a cool shortcut for self-arithmetic operations.

For example instead of writing:

int a = 5;
a = a + 3; // a holds 8

We can simplify it by writing +=:

int a = 5;
a += 3; // a holds 8

The += is adding to a itself the value 3

This operation is valid for all arithmetic operations:

Operator	Shortcut
+	+=
-	-=
*	*=
/	/=
%	%=

Challenge

Beginner

You are given a code with initialization of count. (Don't delete this line!)

Your task is to add the following operations, in this order:

Add 4 to count
Multiply count by 2
Subtract 1 from count

Use the arithmetic shortcuts to do so!

Cheat sheet

Java provides shortcut operators for self-arithmetic operations:

Operator	Shortcut
+	+=
-	-=
*	*=
/	/=
%	%=

Instead of writing:

int a = 5;
a = a + 3; // a holds 8

You can use the shortcut:

int a = 5;
a += 3; // a holds 8

Try it yourself

public class Main {
    public static void main(String[] args) {
        int count = 0;
        
        // Type your code below
        
        
        // Don't change the line below
        System.out.println("count = " + count);
    }
}

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Fundamentals

1Introduction

Java Hello World!Comments Basic Program Structure

4Operators Part 1

Arithmetic Operators Modulo Operator Increment/Decrement Post Increment/DecrementArithmetic ShortcutsComparison Operators String Comparison

7Basic IO

System.out Methods Formatting Output Scanner Class Recap - Till 120 Recap - True or False

10Methods (Functions)

Declaring Methods Method Parameters Return Types Method Overloading Recap - Sigma Function Recap - Validation Function Void Methods

13String Operations

String Methods Part 1 String Methods Part 2 String Formatting String Comparison

2Variables Part 1

Numbers String Boolean char Type Declaration

5Operators Part 2

Logical Operators Part 1 Logical Operators Part 2 Recap - Simple Logic Logical Operators Part 3 Logical Operators Part 4

8Calculator App

Welcome Message Getting Numbers

Basic Operations

Formatted Output

11Arrays Basics

Declaring Arrays Accessing Elements Modifying Arrays Array Methods Recap - Product Array Recap - Reversed Array

14Final Challenges

Number Pattern Pattern Finder Student Grade Calculator

3Variables Part 2

Constants Naming Conventions Recap - Initialize Variables Type Casting Part 1 Type Casting Part 2

6Decision Making

If Statement If - Else Switch Statement Ternary Operator Recap - If Else Nested If - Else

9Loops

For Loop Part 1 While Loop Do While Loop Break Continue For Loop Part 2 Nested Loop Infinite Loop Recap - Dynamic Input

12Iterating Over Arrays

Using For Loop Enhanced For Loop Common Array Operations