Go Arrays

Go Arrays – Complete Tutorial

In Go (Golang), an array is a fixed-size, ordered collection of elements of the same data type.
Arrays are simple, fast, and memory-efficient—often used where size is known in advance.

 What is an Array in Go?

• Stores multiple values of the same type

• Fixed length (cannot grow or shrink)

• Zero-based indexing

• Value type (copied on assignment)

•  Once declared, the size cannot change.

Declaring Arrays

Method-1: Declare with size

Method 2: Initialize with values

Method 3: Size inferred

Accessing Array Elements

•  Accessing out-of-range index causes panic.

 Modifying Array Elements

Looping Through_Arrays

Using for loop

Using range (Recommended)

•  Clean
• Safe
• Interview-friendly

Length of an Array

• len() works on arrays, slices, strings, maps, channels.

 Arrays are Value Types (Very Important)

Assigning one array to another copies all elements.

•  Changes in b do not affect a.

Passing Arrays to Functions

Arrays are passed by value.

•  Use pointer if you want modification.

Multidimensional_Arrays

•  Used in grids, tables, matrices.

Array vs Slice (Interview Favorite)

• Slices are preferred in real applications.

Common Mistakes

•  Expecting_arrays to resize
•  Confusing_arrays with slices
•  Forgetting array size in type
•  Index out of range panic

Interview Questions & MCQs

Q1. Are Go_arrays dynamic?

A) Yes
B) No

Answer: B

Q2. Are arrays_passed by value or reference?

A) Reference
B) Value

Answer: B

Q3. What does [...]int{1,2,3} mean?

A) Error
B) Slice
C) Array with inferred size
D) Pointer

Answer: C

Q4. Which is preferred in Go?

A) Arrays
B) Slices

Answer: B

Q5. Indexing starts from?

A) 1
B) 0

Answer: B

 Real-Life Use Cases

• Fixed-size buffers
• Low-level system code
• Configuration constants
• Embedded systems
•  Performance-critical logic

 Summary

• Arrays are fixed-size collections

• Use zero-based indexing

• Array are value types

• Passed by value to functions

• Rarely used directly—slices preferred

• Important for Go fundamentals & interviews