# Go By Example
<https://gobyexample.com/>


# Assignment 1 - Simple Calculator

## Objective
Write a Go program that performs basic mathematical operations (addition, subtraction, multiplication, and division) based on user input.

## Steps

1. Define constants for valid operations (*add*,*subtract*,*multiply*,*divide*).
2. Use variables to store user inputs and computed results.
3. Use a  loop to allow the user to perform multiple calculations until they choose to exit.
4. Validate inputs using  statements (e.g., handle division by zero).
5. Use a  statement to perform the selected mathematical operation.

## Example Output
```
Enter operation (add, subtract, multiply, divide, exit): add
Enter the first number: 5
Enter the second number: 3
Result: 8

Enter operation (add, subtract, multiply, divide, exit): divide
Enter the first number: 10
Enter the second number: 0
Error: Division by zero is not allowed!

Enter operation (add, subtract, multiply, divide, exit): exit
Goodbye!
```

## Hint
The program can use the `fmt.Scan` function to accept user input.

# Assignment 2 - Inventory Management System

## Objective
Create a program that simulates an inventory management system for a store.

## Steps
1. Define product categories (e.g., Electronics, Groceries, Clothes) using `const` and `iota`.
2. Store a fixed list of initial product names in an **array**.
3. Convert the array into a **slice** so the inventory can grow or shrink dynamically.
4. Use a **map** to associate product names with details like quantity, price, and category.
5. Implement the following **functions**:
    - *AddProduct*: Add a new product to the inventory.
    - *RemoveProduct*: Remove a product from the inventory.
    - *DisplayInventory*: Display all products with their details.
    - *UpdateQuantity*: Update the quantity of a product.

## Example Output
```
Welcome to the Inventory Manager!

Initial Inventory:
1. Laptop - Electronics (Price: $1000, Quantity: 5)
2. Apples - Groceries (Price: $2, Quantity: 50)
3. T-shirt - Clothes (Price: $10, Quantity: 20)

Adding a new product: Phone (Electronics, Price: $800, Quantity: 10)

Updated Inventory:
1. Laptop - Electronics (Price: $1000, Quantity: 5)
2. Apples - Groceries (Price: $2, Quantity: 50)
3. T-shirt - Clothes (Price: $10, Quantity: 20)
4. Phone - Electronics (Price: $800, Quantity: 10)

Updating quantity for Apples: New Quantity = 30

Removing product: T-shirt

Final Inventory:
1. Laptop - Electronics (Price: $1000, Quantity: 5)
2. Apples - Groceries (Price: $2, Quantity: 30)
3. Phone - Electronics (Price: $800, Quantity: 10)
```

- Use **arrays** to store initial product information.
- Use **slices** to dynamically manage items in the inventory.
- Use **maps** to track product details (e.g., quantity or price).
- Define **functions** for adding, removing, and displaying products.
- Use **enums** (via constants) to represent product categories.