/* a */

    function a(text){
        alert(text)
    }
    a("Привет!")

/* cube */

    function cube(number){
        return number ** 3
    }
    let result = cube(prompt('Enter a number'))
    console.log(result)

/* avg2 */

    function avg2(a1, b1) {
        return (a1 + b1) / 2
    }
    let a1 = +prompt('Enter a number')
    let b1 = +prompt('Enter a number')
    avg2(a1, b1)

/* sum3 */

    function sum3(a2 = 0, b2 = 0, c2 = 0) {
    let sum1 = (a2 + b2 + c2)
        return sum1 
    }
    sum3(a2, b2, c2)

/* intRandom */

    function intRandom(a3, b3) {
        let random = Math.random()* (b3-a3) + a3
        return Math.round(random)
    }
    let a3 = +prompt('Enter a number')
    let b3 = +prompt('Enter a number')
    intRandom(a3, b3)

/* greetAll */

    function greetAll() {
        let greetAll1 = " "
            for (let i = 0; i < arguments.length; i++) {
                greetAll1 += " " + arguments[i] + ","
            }
                alert("Hello, " + greetAll1);
        }


    greetAll("superman", "Spiderman", "Бетмен")

/* sum */

    function sum(a4, b4, c4) {
        let sum = 0;
        for (let i = 0; i < arguments.length; i++) {
            sum += arguments[i];
        }
        return sum
        
    }
    a4 = +prompt('Enter a number')
    b4 = +prompt('Enter a number')
    c4 = +prompt('Enter a number') 
    sum(a4, b4, c4)

/* Union */

    function aSample(){
        a("Привет!") 
    }
    
    function cubeSample(){
        cube(5) 
    }
    
    function avg2Sample(){
        avg2(2, 2)
    }
    
    function sum3Sample(){
        sum3(1, 2, 3)
    }
    
    function intRandomSample(){
        intRandom(2,10)
    }
    
    function greetAllSample() {
        greetAll('Superman')
    }
    
    function sumSample(){
        sum(1,4,7)
    }
    
    
    var sample = prompt("Введите название задания")
    switch (sample.toLowerCase()){
        case "a": aSample()
                  break;
        case "cube": cubeSample()
                  break;
        case "avg2": avg2Sample()
                  break;
        case "sum3": sum3Sample()
                  break;
        case "intRandom": intRandomSample()
                  break;
        case "greetAll": greetAllSample()
                  break;
        case "sum": sumSample()
                  break;
    }

/* Union declarative */

    let unionDeclarative = {
        a(){
            a("Привет!")
        },
        cube(){
            cube(5)
        },
        avg2(){
            avg2(2, 2)
        },
        sum3(){
            sum3(1, 2, 3)
        },
        intRandom(){
            intRandom(2,10)
        },
        greetAll(){
            greetAll('Superman')
        },
        sum() {
            sum(1, 4, 7)
        }
    }