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CoCode

Introducing Codi, the AI that codes alongside you in CoCode. Tackle coding problems at Easy, Medium, and Hard levels. Codi compares your code to intended solutions, providing real-time feedback. With an integrated editor, CoCode makes learning to code engaging and effective.

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All Coding Problems

Java Introduction

Learn a basic introduction to the programming language Java and what makes it unique.

Your problem...

Create a Java class called Program that has a main method and prints out "Hello world".
Start Coding (Easy)

Choose your difficulty:

Access Modifiers

Private? Public? Protected? What are all of those keywords and what do they have to do with coding?!

Your problem...

Make a class have a variable called name, and another integer variable that is a balance; No main method.
Start Coding (Easy)

Choose your difficulty:

Defining Numbers

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Booleans

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Create a Java program that declares a boolean variable `isSunny` and initializes it to true. Print out the value of `isSunny`.
Start Coding (Easy)

Choose your difficulty:

Defining Strings

Learn how to define strings in Java, and use the .substring() method to manipulate string data.

Your problem...

Start Coding (Easy)

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Defining Characters

Learn how to define characters in Java using the char data type, and understand basic operations and conversions involving characters.

Your problem...

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If Statement

Learn how to use conditional statements in Java to make decisions based on different conditions.

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For Loop

Explore the usage of for loops in Java for iterating over arrays and collections or executing a block of code a fixed number of times.

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While Loop

Understand the syntax and usage of while loops in Java for executing a block of code repeatedly as long as a specified condition is true.

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Do-While Loop

Learn about the do-while loop in Java, which executes a block of code once, and then repeats the loop as long as a specified condition is true.

Your problem...

Start Coding (Easy)

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For-Each Loop

Explore the for-each loop (enhanced for loop) in Java for iterating over elements in arrays or collections.

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Switch Statement

Understand how to use switch statements in Java for multi-way branching based on the value of an expression.

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Simplifying Boolean Expressions

Learn how to simplify Boolean expressions using De Morgan's laws, which state the equivalence between negating logical conjunctions (AND) and disjunctions (OR), and vice versa.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Short-Circuit Evaluation

Understand short-circuit evaluation in Java and other programming languages, where the evaluation of Boolean expressions stops as soon as the outcome is determined by the initial conditions, improving efficiency and avoiding unnecessary computations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Declaration vs Instantiation

Learn about the difference between declaring and instantiating variables and objects in Java. Declaration refers to specifying the type and name of a variable or object without allocating memory, while instantiation involves creating an instance of a class or allocating memory for an object.

Your problem...

Start Coding (Easy)

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Methods

Explore defining methods, passing arguments, returning values, and method overloading.

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Arrays and ArrayLists

Master the use of arrays and ArrayLists in Java, including common operations and algorithms.

Your problem...

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ArrayLists

Learn how to use ArrayLists in Java, a resizable array implementation of the List interface.

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Arrays

Explore how to declare, initialize, and manipulate one-dimensional arrays in Java.

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2D Arrays

Learn how to declare, initialize, and work with two-dimensional arrays (arrays of arrays) in Java.

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Object-Oriented Programming

Introduction to classes, objects, and relational hierarchies.

Your problem...

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Writing Classes

Learn the fundamentals of writing classes in Java, including constructors, fields, methods, and encapsulation.

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Constructors

Learn about constructors in Java, including default constructors, parameterized constructors, constructor chaining, and best practices.

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this Keyword

Understand the 'this' keyword in Java, its usage to refer to the current object, and resolving ambiguity between instance variables and parameters.

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Scope

Learn about variable scope in Java, including local variables, instance variables, class (static) variables, and block scope.

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Using Classes

Explore how to effectively use classes in Java for creating objects, accessing fields and methods, and implementing inheritance.

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Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

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Run vs Compile Time

Understand the difference between run time and compile time in software development.

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Recursion

Understand recursive methods, recursion vs. iteration, and solving problems recursively.

Your problem...

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Exceptions and Error Handling

Learn how to handle exceptions using try-catch blocks and understanding checked vs. unchecked exceptions.

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Wrapper Classes

Explore Wrapper Classes in Java, which allow you to use primitive data types as objects.

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Static vs Non-Static

Learn what the difference is between static and non-static features in Java.

Your problem...

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Initialization Vs Declaration

Learn the ins and outs of when to look for Initialization Vs Declaration.

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Superclass Vs Subclass

Learn the difference and the relationship between a superclass and its subclass.

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Polymorphism

Learn deeper about the comparison of a parent class to its child class.

Your problem...

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Encapsulation

Further your knowledge when dealing with parent-child class relationships.

Your problem...

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Enums

Learn how to define and use enums in Java to represent a fixed set of constants.

Your problem...

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++i vs i++

Understand the difference between pre-increment and post-increment operations.

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Personalized

Java Introduction

Learn a basic introduction to the programming language Java and what makes it unique.

Your problem...

Create a Java class called Program that has a main method and prints out "Hello world".
Start Coding (Easy)

Choose your difficulty:

Access Modifiers

Private? Public? Protected? What are all of those keywords and what do they have to do with coding?!

Your problem...

Make a class have a variable called name, and another integer variable that is a balance; No main method.
Start Coding (Easy)

Choose your difficulty:

Defining Numbers

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Booleans

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Create a Java program that declares a boolean variable `isSunny` and initializes it to true. Print out the value of `isSunny`.
Start Coding (Easy)

Choose your difficulty:

Defining Strings

Learn how to define strings in Java, and use the .substring() method to manipulate string data.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Characters

Learn how to define characters in Java using the char data type, and understand basic operations and conversions involving characters.

Your problem...

Start Coding (Easy)

Choose your difficulty:

If Statement

Learn how to use conditional statements in Java to make decisions based on different conditions.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For Loop

Explore the usage of for loops in Java for iterating over arrays and collections or executing a block of code a fixed number of times.

Your problem...

Start Coding (Easy)

Choose your difficulty:

While Loop

Understand the syntax and usage of while loops in Java for executing a block of code repeatedly as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Do-While Loop

Learn about the do-while loop in Java, which executes a block of code once, and then repeats the loop as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For-Each Loop

Explore the for-each loop (enhanced for loop) in Java for iterating over elements in arrays or collections.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Switch Statement

Understand how to use switch statements in Java for multi-way branching based on the value of an expression.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Simplifying Boolean Expressions

Learn how to simplify Boolean expressions using De Morgan's laws, which state the equivalence between negating logical conjunctions (AND) and disjunctions (OR), and vice versa.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Short-Circuit Evaluation

Understand short-circuit evaluation in Java and other programming languages, where the evaluation of Boolean expressions stops as soon as the outcome is determined by the initial conditions, improving efficiency and avoiding unnecessary computations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Declaration vs Instantiation

Learn about the difference between declaring and instantiating variables and objects in Java. Declaration refers to specifying the type and name of a variable or object without allocating memory, while instantiation involves creating an instance of a class or allocating memory for an object.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Methods

Explore defining methods, passing arguments, returning values, and method overloading.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays and ArrayLists

Master the use of arrays and ArrayLists in Java, including common operations and algorithms.

Your problem...

Start Coding (Easy)

Choose your difficulty:

ArrayLists

Learn how to use ArrayLists in Java, a resizable array implementation of the List interface.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays

Explore how to declare, initialize, and manipulate one-dimensional arrays in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

2D Arrays

Learn how to declare, initialize, and work with two-dimensional arrays (arrays of arrays) in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Object-Oriented Programming

Introduction to classes, objects, and relational hierarchies.

Your problem...

Start Coding (Easy)

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Writing Classes

Learn the fundamentals of writing classes in Java, including constructors, fields, methods, and encapsulation.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Constructors

Learn about constructors in Java, including default constructors, parameterized constructors, constructor chaining, and best practices.

Your problem...

Start Coding (Easy)

Choose your difficulty:

this Keyword

Understand the 'this' keyword in Java, its usage to refer to the current object, and resolving ambiguity between instance variables and parameters.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Scope

Learn about variable scope in Java, including local variables, instance variables, class (static) variables, and block scope.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Using Classes

Explore how to effectively use classes in Java for creating objects, accessing fields and methods, and implementing inheritance.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Run vs Compile Time

Understand the difference between run time and compile time in software development.

Your problem...

Start Coding (Easy)

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Recursion

Understand recursive methods, recursion vs. iteration, and solving problems recursively.

Your problem...

Start Coding (Easy)

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Exceptions and Error Handling

Learn how to handle exceptions using try-catch blocks and understanding checked vs. unchecked exceptions.

Your problem...

Start Coding (Easy)

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Wrapper Classes

Explore Wrapper Classes in Java, which allow you to use primitive data types as objects.

Your problem...

Start Coding (Easy)

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Static vs Non-Static

Learn what the difference is between static and non-static features in Java.

Your problem...

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Initialization Vs Declaration

Learn the ins and outs of when to look for Initialization Vs Declaration.

Your problem...

Start Coding (Easy)

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Superclass Vs Subclass

Learn the difference and the relationship between a superclass and its subclass.

Your problem...

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Polymorphism

Learn deeper about the comparison of a parent class to its child class.

Your problem...

Start Coding (Easy)

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Encapsulation

Further your knowledge when dealing with parent-child class relationships.

Your problem...

Start Coding (Easy)

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Enums

Learn how to define and use enums in Java to represent a fixed set of constants.

Your problem...

Start Coding (Easy)

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++i vs i++

Understand the difference between pre-increment and post-increment operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

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Card Content

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Card Title

Card Description

Card Content

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Basics

Java Introduction

Learn a basic introduction to the programming language Java and what makes it unique.

Your problem...

Create a Java class called Program that has a main method and prints out "Hello world".
Start Coding (Easy)

Choose your difficulty:

Access Modifiers

Private? Public? Protected? What are all of those keywords and what do they have to do with coding?!

Your problem...

Make a class have a variable called name, and another integer variable that is a balance; No main method.
Start Coding (Easy)

Choose your difficulty:

Defining Numbers

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Booleans

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Create a Java program that declares a boolean variable `isSunny` and initializes it to true. Print out the value of `isSunny`.
Start Coding (Easy)

Choose your difficulty:

Defining Strings

Learn how to define strings in Java, and use the .substring() method to manipulate string data.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Characters

Learn how to define characters in Java using the char data type, and understand basic operations and conversions involving characters.

Your problem...

Start Coding (Easy)

Choose your difficulty:

If Statement

Learn how to use conditional statements in Java to make decisions based on different conditions.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For Loop

Explore the usage of for loops in Java for iterating over arrays and collections or executing a block of code a fixed number of times.

Your problem...

Start Coding (Easy)

Choose your difficulty:

While Loop

Understand the syntax and usage of while loops in Java for executing a block of code repeatedly as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Do-While Loop

Learn about the do-while loop in Java, which executes a block of code once, and then repeats the loop as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For-Each Loop

Explore the for-each loop (enhanced for loop) in Java for iterating over elements in arrays or collections.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Switch Statement

Understand how to use switch statements in Java for multi-way branching based on the value of an expression.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Declaration vs Instantiation

Learn about the difference between declaring and instantiating variables and objects in Java. Declaration refers to specifying the type and name of a variable or object without allocating memory, while instantiation involves creating an instance of a class or allocating memory for an object.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Methods

Explore defining methods, passing arguments, returning values, and method overloading.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays

Explore how to declare, initialize, and manipulate one-dimensional arrays in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Object-Oriented Programming

Introduction to classes, objects, and relational hierarchies.

Your problem...

Start Coding (Easy)

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Writing Classes

Learn the fundamentals of writing classes in Java, including constructors, fields, methods, and encapsulation.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Constructors

Learn about constructors in Java, including default constructors, parameterized constructors, constructor chaining, and best practices.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Scope

Learn about variable scope in Java, including local variables, instance variables, class (static) variables, and block scope.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Run vs Compile Time

Understand the difference between run time and compile time in software development.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Initialization Vs Declaration

Learn the ins and outs of when to look for Initialization Vs Declaration.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Data Types

Defining Numbers

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Booleans

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Create a Java program that declares a boolean variable `isSunny` and initializes it to true. Print out the value of `isSunny`.
Start Coding (Easy)

Choose your difficulty:

Defining Strings

Learn how to define strings in Java, and use the .substring() method to manipulate string data.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Characters

Learn how to define characters in Java using the char data type, and understand basic operations and conversions involving characters.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Enums

Learn how to define and use enums in Java to represent a fixed set of constants.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Variables

Defining Numbers

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Booleans

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Create a Java program that declares a boolean variable `isSunny` and initializes it to true. Print out the value of `isSunny`.
Start Coding (Easy)

Choose your difficulty:

Defining Strings

Learn how to define strings in Java, and use the .substring() method to manipulate string data.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Defining Characters

Learn how to define characters in Java using the char data type, and understand basic operations and conversions involving characters.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Declaration vs Instantiation

Learn about the difference between declaring and instantiating variables and objects in Java. Declaration refers to specifying the type and name of a variable or object without allocating memory, while instantiation involves creating an instance of a class or allocating memory for an object.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Scope

Learn about variable scope in Java, including local variables, instance variables, class (static) variables, and block scope.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Wrapper Classes

Explore Wrapper Classes in Java, which allow you to use primitive data types as objects.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Initialization Vs Declaration

Learn the ins and outs of when to look for Initialization Vs Declaration.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Enums

Learn how to define and use enums in Java to represent a fixed set of constants.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Operators

Defining Numbers

Learn how to define numbers in Java, and explore their arithmetic operations.

Your problem...

Start Coding (Easy)

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++i vs i++

Understand the difference between pre-increment and post-increment operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

String Manipulation

Defining Strings

Learn how to define strings in Java, and use the .substring() method to manipulate string data.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Control Statements

If Statement

Learn how to use conditional statements in Java to make decisions based on different conditions.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For Loop

Explore the usage of for loops in Java for iterating over arrays and collections or executing a block of code a fixed number of times.

Your problem...

Start Coding (Easy)

Choose your difficulty:

While Loop

Understand the syntax and usage of while loops in Java for executing a block of code repeatedly as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Do-While Loop

Learn about the do-while loop in Java, which executes a block of code once, and then repeats the loop as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For-Each Loop

Explore the for-each loop (enhanced for loop) in Java for iterating over elements in arrays or collections.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Switch Statement

Understand how to use switch statements in Java for multi-way branching based on the value of an expression.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Loops

For Loop

Explore the usage of for loops in Java for iterating over arrays and collections or executing a block of code a fixed number of times.

Your problem...

Start Coding (Easy)

Choose your difficulty:

While Loop

Understand the syntax and usage of while loops in Java for executing a block of code repeatedly as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Do-While Loop

Learn about the do-while loop in Java, which executes a block of code once, and then repeats the loop as long as a specified condition is true.

Your problem...

Start Coding (Easy)

Choose your difficulty:

For-Each Loop

Explore the for-each loop (enhanced for loop) in Java for iterating over elements in arrays or collections.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Functions

Methods

Explore defining methods, passing arguments, returning values, and method overloading.

Your problem...

Start Coding (Easy)

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Boolean Logic

Simplifying Boolean Expressions

Learn how to simplify Boolean expressions using De Morgan's laws, which state the equivalence between negating logical conjunctions (AND) and disjunctions (OR), and vice versa.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Short-Circuit Evaluation

Understand short-circuit evaluation in Java and other programming languages, where the evaluation of Boolean expressions stops as soon as the outcome is determined by the initial conditions, improving efficiency and avoiding unnecessary computations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

++i vs i++

Understand the difference between pre-increment and post-increment operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Collections

For-Each Loop

Explore the for-each loop (enhanced for loop) in Java for iterating over elements in arrays or collections.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays and ArrayLists

Master the use of arrays and ArrayLists in Java, including common operations and algorithms.

Your problem...

Start Coding (Easy)

Choose your difficulty:

ArrayLists

Learn how to use ArrayLists in Java, a resizable array implementation of the List interface.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays

Explore how to declare, initialize, and manipulate one-dimensional arrays in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

2D Arrays

Learn how to declare, initialize, and work with two-dimensional arrays (arrays of arrays) in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Data Structures

Arrays and ArrayLists

Master the use of arrays and ArrayLists in Java, including common operations and algorithms.

Your problem...

Start Coding (Easy)

Choose your difficulty:

ArrayLists

Learn how to use ArrayLists in Java, a resizable array implementation of the List interface.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays

Explore how to declare, initialize, and manipulate one-dimensional arrays in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

2D Arrays

Learn how to declare, initialize, and work with two-dimensional arrays (arrays of arrays) in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Intermediate Concepts

Simplifying Boolean Expressions

Learn how to simplify Boolean expressions using De Morgan's laws, which state the equivalence between negating logical conjunctions (AND) and disjunctions (OR), and vice versa.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Short-Circuit Evaluation

Understand short-circuit evaluation in Java and other programming languages, where the evaluation of Boolean expressions stops as soon as the outcome is determined by the initial conditions, improving efficiency and avoiding unnecessary computations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Arrays and ArrayLists

Master the use of arrays and ArrayLists in Java, including common operations and algorithms.

Your problem...

Start Coding (Easy)

Choose your difficulty:

ArrayLists

Learn how to use ArrayLists in Java, a resizable array implementation of the List interface.

Your problem...

Start Coding (Easy)

Choose your difficulty:

2D Arrays

Learn how to declare, initialize, and work with two-dimensional arrays (arrays of arrays) in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

this Keyword

Understand the 'this' keyword in Java, its usage to refer to the current object, and resolving ambiguity between instance variables and parameters.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Recursion

Understand recursive methods, recursion vs. iteration, and solving problems recursively.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Exceptions and Error Handling

Learn how to handle exceptions using try-catch blocks and understanding checked vs. unchecked exceptions.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Wrapper Classes

Explore Wrapper Classes in Java, which allow you to use primitive data types as objects.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Static vs Non-Static

Learn what the difference is between static and non-static features in Java.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Superclass Vs Subclass

Learn the difference and the relationship between a superclass and its subclass.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Polymorphism

Learn deeper about the comparison of a parent class to its child class.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Encapsulation

Further your knowledge when dealing with parent-child class relationships.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Enums

Learn how to define and use enums in Java to represent a fixed set of constants.

Your problem...

Start Coding (Easy)

Choose your difficulty:

++i vs i++

Understand the difference between pre-increment and post-increment operations.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Object-Oriented Programming

Access Modifiers

Private? Public? Protected? What are all of those keywords and what do they have to do with coding?!

Your problem...

Make a class have a variable called name, and another integer variable that is a balance; No main method.
Start Coding (Easy)

Choose your difficulty:

Declaration vs Instantiation

Learn about the difference between declaring and instantiating variables and objects in Java. Declaration refers to specifying the type and name of a variable or object without allocating memory, while instantiation involves creating an instance of a class or allocating memory for an object.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Object-Oriented Programming

Introduction to classes, objects, and relational hierarchies.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Writing Classes

Learn the fundamentals of writing classes in Java, including constructors, fields, methods, and encapsulation.

Your problem...

Start Coding (Easy)

Choose your difficulty:

Constructors

Learn about constructors in Java, including default constructors, parameterized constructors, constructor chaining, and best practices.

Your problem...

Start Coding (Easy)

Choose your difficulty:

this Keyword

Understand the 'this' keyword in Java, its usage to refer to the current object, and resolving ambiguity between instance variables and parameters.

Your problem...

Start Coding (Easy)

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Using Classes

Explore how to effectively use classes in Java for creating objects, accessing fields and methods, and implementing inheritance.

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Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

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Static vs Non-Static

Learn what the difference is between static and non-static features in Java.

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Superclass Vs Subclass

Learn the difference and the relationship between a superclass and its subclass.

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Polymorphism

Learn deeper about the comparison of a parent class to its child class.

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Encapsulation

Further your knowledge when dealing with parent-child class relationships.

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Classes and Objects

Access Modifiers

Private? Public? Protected? What are all of those keywords and what do they have to do with coding?!

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Make a class have a variable called name, and another integer variable that is a balance; No main method.
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Writing Classes

Learn the fundamentals of writing classes in Java, including constructors, fields, methods, and encapsulation.

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Constructors

Learn about constructors in Java, including default constructors, parameterized constructors, constructor chaining, and best practices.

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Using Classes

Explore how to effectively use classes in Java for creating objects, accessing fields and methods, and implementing inheritance.

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Inheritance

Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

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Superclass Vs Subclass

Learn the difference and the relationship between a superclass and its subclass.

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Polymorphism

Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

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Polymorphism

Learn deeper about the comparison of a parent class to its child class.

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Encapsulation

Access Modifiers

Private? Public? Protected? What are all of those keywords and what do they have to do with coding?!

Your problem...

Make a class have a variable called name, and another integer variable that is a balance; No main method.
Start Coding (Easy)

Choose your difficulty:

Advanced Object-Oriented Programming

Introduction to classes, objects, inheritance, polymorphism, and encapsulation in Java.

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Encapsulation

Further your knowledge when dealing with parent-child class relationships.

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Algorithms

Recursion

Understand recursive methods, recursion vs. iteration, and solving problems recursively.

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Exception Handling

Exceptions and Error Handling

Learn how to handle exceptions using try-catch blocks and understanding checked vs. unchecked exceptions.

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