Defining Arrays
C
C++
C#
F#
Go
Java
JavaScript
Kotlin
Rust
C
int numbers1[4];
int numbers2[4] = { 1, 2, 3, 5 }; // with initialization
int numbers3[] = { 1, 2, 3, 5 }; // without specifying size
C++
int numbers1[4];
int numbers2[4] { 1, 2, 3, 5 }; // with initialization
int numbers3[] { 1, 2, 3, 5 }; // without specifying size
C#
int[] numbers1; // array without initialization
int[] numbers2 = new int[4]; // with size and default initialization
int[] numbers3 = new int[4] { 1, 2, 3, 5 }; // with explicit initialization
int[] numbers4 = new int[] { 1, 2, 3, 5 };
int[] numbers5 = new[] { 1, 2, 3, 5 };
int[] numbers6 = { 1, 2, 3, 5 };
int[] numbers7 = [1, 2, 3, 5 ]; // collection expressions (starting with C# 12)
int[] numbers8 = []; // empty array
F#
let numbers1 = [||] // empty array
let numbers2 = [|1; 2; 3; 4; 5|] // with initialization
// initialization using an expression
let numbers3 = [| for i in 1..5 -> i * i |] // [|1; 4; 9; 16; 25|]
// initialization using Array type functions
let numbers4 = Array.create 5 1 // [|1; 1; 1; 1; 1|]
let numbers5 = Array.init 5 (fun i -> i * i) // [|1; 4; 9; 16; 25|]
let numbers6: int array = Array.zeroCreate 5 // [|0; 0; 0; 0; 0|]
Go
package main
import "fmt"
func main() {
var numbers1 []int // empty array (slice)
var numbers2 [5]int // array of five int elements
var numbers3 = [5]int{1,2,3,4,5}
var numbers4 = [...]int{1,2,3,4,5} // array length is calculated automatically
fmt.Println(numbers1) // []
fmt.Println(numbers2) // [0 0 0 0 0]
fmt.Println(numbers3) // [1 2 3 4 5]
fmt.Println(numbers4) // [1 2 3 4 5]
}
Java
int[] numbers1; // array without initialization
int numbers2[];
int[] numbers3 = new int[4]; // with size and default initialization
int numbers4[] = new int[4];
int[] numbers5 = new int[] { 1, 2, 3, 5 }; // with explicit initialization
int numbers6[] = new int[] { 1, 2, 3, 5 }; // with explicit initialization
int[] numbers7 = { 1, 2, 3, 5 };
int numbers8[] = { 1, 2, 3, 5 };
int[] numbers9 = {}; // empty array
int numbers10[] = {};
JavaScript
const numbers1 = []; // empty array
const numbers2 = [1, 2, 3, 4, 5 ];
const numbers3 = new Array(1, 2, 3, 4, 5); // using the Array constructor
Kotlin
val number1: Array<Int> // array without initialization
val numbers2 = arrayOfNulls<Int>(4) // with size and default initialization
val numbers3 = arrayOf(1, 2, 3, 5); // with explicit initialization
val numbers4: Array<Int> = arrayOf(1, 2, 3, 5); // with explicit initialization and typing
var i = 0;
val numbers5 = Array(3, { i++ * 2}) // generation of elements based on an expression
Rust
let numbers1: [i32; 5] = [0;5]; // with type and size, initialized with a single value
let numbers2 = [1, 2, 3, 4, 5 ]; // with explicit initialization
let numbers3: [i32; 5] = [1, 2, 3, 4, 5 ]; // with explicit initialization and size
Next