C

int x = 2;
     
switch(x)
{
    case 1: 
        printf("x = 1 \n");
        break;
    case 2: 
        printf("x = 2 \n");
        break;
    case 3: 
        printf("x = 3 \n");
        break;
    default: 
        printf("x is undefined \n");
        break;
}

C++

#include <iostream> 

int main()
{
    int x = 2;
     
    switch(x)
    {
        case 1: 
            std::cout << "x = 1" << std::endl;
            break;
        case 2: 
            std::cout << "x = 2" << std::endl;
            break;
        case 3: 
            std::cout << "x = 3" << std::endl;
            break;
        default: 
            std::cout << "x is undefined" << std::endl;
            break;
    }

    // switch-case с инициализацией переменной
    char op = '+';
    int n = 10;
    switch(int k{2}; op)
    {
        case '+':
            std::cout << n + k << std::endl;
            break;
        case '-':
            std::cout << n - k << std::endl;
            break;
        case '*':
            std::cout << n * k << std::endl;
            break;
    }
}

C#

int x = 2;
     
switch(x)
{    
    case 1: 
        Console.WriteLine("x = 1");
        break;
    case 2: 
        Console.WriteLine("x = 2");
        break;
    case 3: 
        Console.WriteLine("x = 3");
        break;
    default: 
        Console.WriteLine("x is undefined");
        break;
}

Возвращение из switch:

int x = 2;
int result = x switch {
    1 => 1,
    2 => 4,
    3 => 9,
    _ => -1
};
Console.WriteLine(result);  // 4

Dart

int x = 2;
     
switch(x){
    
    case 1: 
        print("x = 1");
    case 2: 
        print("x = 2");
    case 3: 
        print("x = 3");
    default: 
        print("x is undefined");
}

F#

let x = 2

match x with
| 1 ->  printfn "x = 1"
| 2 ->  printfn "x = 2"
| 3 ->  printfn "x = 3"
| _ -> printfn "x is undefined"

Возвращение из match:

let x = 2
 
let result = match x with
             | 1 -> 1
             | 2 -> 4
             | 3 -> 9
             | _ -> -1
 
printfn "%d" result     // 4

JavaScript

const x = 2;
     
switch(x)
{
    case 1: 
        console.log("x = 1");
        break;
    case 2: 
        console.log("x = 2");
        break;
    case 3: 
        console.log("x = 3");
        break;
    default: 
        console.log("x is undefined");
        break;
}

Kotlin

val x = 2

when (x) {
    1 -> println("x = 1")
    2 -> println("x = 2")
    3 -> println("x = 3")
    else -> print("x is undefined")
}

Возвращение из when:

val x = 2

val result = when (x) {
    1 -> 1
    2 -> 4
    3 -> 9
    else -> -1
}

println(result)

Python

x = 2
     
match x:
    case 1: 
        print("x = 1")
    case 2: 
        print("x = 2")
    case 3: 
        print("x = 3")
    case _: 
        print("x is undefined")

Rust

fn main(){
  
    let x = 2;

    match x {
        1 => println!("x = 1"),
        2 => println!("x = 2"),
        3 => println!("x = 3"),
        _ => println!("x is undefined")
    }
}

Возвращение из match:

fn main(){
  
    let x = 2;
    let result =  match x {
        1 => 1,
        2 => 4,
        3 => 9,
        _ =>-1
    };
    println!("{}", result);
}