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Recap - Declaring Variables

Part of the Fundamentals section of Coddy's Dart journey — lesson 15 of 94.

Challenge

Easy

In this challenge, you'll create a simple data model for a weather application using various variable types and concepts you've learned.

Complete the following tasks:

Create a String variable named cityName with the value "New York"
Create an int variable named temperature with the value 28
Create a double variable named humidity with the value 0.65
Create a bool variable named isSunny with the value true
Create a variable using var named weatherCondition with the value "Partly Cloudy"
Create a final variable named countryCode with the value "US"
Create a const variable named WEATHER_API_VERSION with the value "v1.0" (use proper naming convention for constants)
Create a nullable String variable named weatherWarning with the value null
Print all variables with descriptive labels in the exact format shown in the expected output
Update weatherWarning to "Heat Advisory" and print it again with the same label

Your output must match the exact format shown in the expected output.

Try it yourself

void main() {
  // Declare all required variables
  String cityName = ?;
  int temperature = ?;
  double humidity = ?;
  bool isSunny = ?;
  var weatherCondition = ?;
  final countryCode = ?;
  const String WEATHER_API_VERSION = ?;
  String? weatherWarning = ?;
  
  // Print all variables with labels
  print("Weather Information:");
  print("City: ?");
  print("Temperature: $temperature°C");
  print("Humidity: ?");
  print("Sunny: ?");
  print("Condition: ?");
  print("Country: ?");
  print("API Version: ?");
  print("Warning: ?");
  
  // Update weatherWarning and print it again
  weatherWarning = ?;
  print("Warning: ?");
}

All lessons in Fundamentals

1Introduction to Dart

What is Dart?The main Function Printing Output Code Comments

4Operators Part 2

Comparison Operators Logical AND Logical OR Logical NOT Type Test Operators Recap - Making Comparisons

7Working with Strings

String Concatenation String Interpolation Multi-line Strings String Properties Basic String Methods

10Collections - Maps Basics

What are Maps?Creating a Map Accessing Values by Key Key-Value Pairs Getting Map Size Getting Keys Getting Values Checking if a Key Exists

13Null Safety In Depth

Understanding Null Nullable Types Non-Nullable Types Null Assertion Operator Late Initialization Recap - Handling Null Safely

16Fundamentals Challenges

Challenge: List of calculation Challenge: Sum of numbers Challenge: Find product

2Variables and Basic Data Types

What are Variables?Strings Integers (int)Doubles (double)Booleans (bool)Type Inference with 'var'Final Variables Constant Variables Naming Conventions Basic Null SafetyRecap - Declaring Variables

5Operators Part 3

Null-aware Operator Null-aware Access Conditional Operator

8Control Flow - Loops

The 'for' Loop The 'while' Loop The 'do-while' Loop Using 'break' in Loops Using 'continue' in Loops Recap - Repeating Code

11Functions Basics

What are Functions?Defining a Basic Function Calling a Function Functions with Parameters Functions Returning Values The 'void' Keyword Arrow Syntax Recap - Simple Functions

14Type Conversion

Converting String to int Converting String to double Converting Numbers to String Handling Conversion Errors

3Operators Part 1

Arithmetic Operators Integer Division Modulo Operator Increment and Decrement Assignment Shortcuts Recap - Simple Calculations

6Control Flow - Decision Making

The 'if' Statement The 'else' Statement The 'else if' Statement Recap - Simple Decisions Nested 'if' Statements The 'switch' Statement

9Collections - Lists Basics

What are Lists?Creating a List Accessing by Index Getting List Length Adding Elements Removing Elements Checking if a List is Empty Iterating Over a List

12Functions Advanced

Optional Positional Parameters Named Parameters Required Named Parameters Default Parameter Values Recap - Function Parameters

15Project: Simple Calculator

Setting Up Declaring Number

Project lesson

Creating an Operation

Project lesson

Performing Calculation

Project lesson

Displaying Result

Project lesson