### Printing Hello World

Create a function that prints 'Hello, world!' to the console using Rust.

### Declaring Variables

Learn to declare immutable variables in Rust and understand their usage.

### Mutable Variables

Define and modify mutable variables in Rust.

### Constants

Learn how to define and use constants in Rust.

### Primitive Data Types

Get familiar with primitive data types in Rust by defining and annotating variables.

### Converting Numerical Types

Implement a function to convert numerical types using the `as` keyword in Rust.

### Mathematical operations

Practice mathematical operations in Rust, including addition, subtraction, multiplication, and division.

### Sum of Array

Calculate the sum of all elements in an array.

### Tuples

Create a function that returns a tuple of values.

### The Unit Type

Understand and use the unit type `()` in Rust.

### Functions

Implement and work with functions in Rust.

### Closures

Learn how to define and use closures in Rust.

### Control Flow

Implement basic control flow in Rust using if-else statements.

### Basic If-Else Statements

Learn how to use if-else statements in Rust to control the flow of your program.

### Sum of Even Numbers

Implement a function to sum even numbers in a given range using a for loop.

### Countdown

Implement a countdown timer using a while loop in Rust.

### Weekday from Number

Use Rust's pattern matching to determine the weekday given its number.

### Ownership

Understand and implement Rust's ownership model.

### Mutable References

Implement Rust's ownership model with mutable references.

### Ownership Rules

Identify and fix ownership rule violations in Rust code.

### Character counting string

Write a program that takes a string as input and counts the number of characters in the string.

### Fizz Buzz

Write a program that prints 'Fizz' for multiples of three, 'Buzz' for multiples of five, and 'FizzBuzz' for multiples of both.

### Fibonacci

Write a function that returns the nth number in the Fibonacci sequence.

### The From trait

Implement the From trait for a custom type.

### Animal sanctuary registry

Create a program that manages a registry of animals in a sanctuary.

### Median and mode

Write a program that calculates the median and mode of a list of numbers.

### Graceful error handling

Implement graceful error handling in Rust using the Result type.

### Is Prime

Implement a function to check if a number is prime using logical operators and conditional statements.

### Determine Number Characteristics

Implement a function to describe if a number is positive, negative, or zero, and if it is even or odd.

### Factorial Calculator

Implement a function to calculate the factorial of a non-negative integer using early returns and loops.

### Temperature Converter

Implement a temperature converter that handles various units and errors.

### Validate User Input

Implement early returns in Rust to validate user input for age and email.

### Find the First Palindrome

Implement a function to find the first palindrome number in a range using any control flow construct.

### Finite State Automaton

Implement a finite state automaton (FSA) to recognize a specific pattern in a sequence of characters.

### Maze Solver

Implement a maze solver using control flow in Rust to navigate through a maze represented as a grid.