Exercise 4: Arrays, Slices, and Maps in Go

Understanding Arrays, Slices, and Maps in Go

In Go, arrays are fixed-size collections. Once declared, their size cannot change.

Slices, on the other hand, are dynamic arrays that can grow or shrink as needed using the append() function.

Maps are key-value data structures, similar to dictionaries in Python or objects in JavaScript.

Comparison with other languages:

• Arrays: In Go, arrays have a fixed size, unlike Python lists or JavaScript arrays, which are dynamic.
• Slices: Unlike Python lists, Go slices give more control over memory management.
• Maps: Go maps function similarly to Python dictionaries and JavaScript objects.

For more details, check the official Go documentation: Go Documentation

Instructions:

• 1️⃣ Create a file named arrays_slices_maps.go in your Go project.
• 2️⃣ Declare a fixed-size array, a dynamic slice, and a map.
• 3️⃣ Print the content of these structures to the console.

package main

import "fmt"

func main() {
    // 1. Array
    var array [3]int = [3]int{1, 2, 3}
    fmt.Println("Array:", array)
    
    // 2. Slice
    var slice = []string{"Go", "Rust", "Python"}
    slice = append(slice, "JavaScript")  // Add an element
    fmt.Println("Slice after append:", slice)
    
    // 3. Map
    var myMap = make(map[string]int)
    myMap["Go"] = 1
    myMap["Rust"] = 2
    fmt.Println("Map example:", myMap)
}

• 4️⃣ Run the program using the command: go run arrays_slices_maps.go

Code Explanation:

1️⃣ var array [3]int = [3]int{1, 2, 3} : Declares a fixed-size array with 3 elements.

2️⃣ var slice = []string{"Go", "Rust", "Python"} : Declares a dynamic slice and appends an element using append().

3️⃣ var myMap = make(map[string]int) : Creates an empty map of type string → int. Elements are added using myMap["Go"] = 1.

4️⃣ fmt.Println() : Prints the values of our array, slice, and map to the console.