Javascript

{
    //true, false, 1, "1",  0, "0", null, undefined, [], {}
    if(true){
       document.write("실행되었습니다.(true)");
    } else {
        document.write("실행되었습니다.(false)");
    }
}

{
    const num = 100;

    if( num == 100 ) document.write("실행되었습니다.(true)"); 
    else document.write("실행되었습니다.(false)");
}

{
    const num = 100;

    if(num == 90){
        document.write("실행되었습니다.(num==90)")
    } else if (num == 100) {
        document.write("실행되었습니다.(num==100)")
    } else if (num == 110) {
        document.write("실행되었습니다.(num==110)")
    } else if (num == 120) {
        document.write("실행되었습니다.(num==120)")
    } else {
        document.write("실행되었습니다.(num==값이없음)")
    }
}

{
    const num = 100;

    if(num == 100){
        document.write("실행되었습니다(1)");
        if(num == 100){
            document.write("실행되었습니다(2)");
            if(num == 100){
                document.write("실행되었습니다(3)");
            }
        }   
    } else {
        document.write("실행되었습니다(4)");
    }
}

{
    const num = 100;

    if (num == 100){
        document.write("true");
    } else {
        document.write("false");
    }    

    (num == 100) ? document.write("true") : document.write("false");
}

{
    const num = 100;

    switch (num){
        case 100 :
            document.write("실행되었습니다(num==100)");
        break;
        case 200 :
            document.write("실행되었습니다(num==200)");  
        break;
        case 300 :
            document.write("실행되었습니다(num==300)"); 
        break;
        default :
            document.write("실행되었습니다(num==값이없음)"); 
        break;
    }
}

{
    let num = 1;

    while(num <= 10 ){
        document.write( num + ". 실행되었습니다.");
        num++;
    }    
}

{
    let num = 1;

    do {
        document.write( num + ". 실행되었습니다.");
        num++;
    } while (num <= 10)
}

{
    for(let i=1; i<=10; i++){
        document.write(i + ".실행되었습니다.");
    }
}

{
    for(let i=1; i<=2; i++){
        document.write(i + ".실행(i)되었습니다.");
        for(let j=1; j<=3; j++){
            document.write(j + ".실행(j)되었습니다.");
        }
    }
}

{
    let num = 1;
    while(num <= 20){
        document.write(num);
        if(num == 10){
            break;
        }
        num++;
    }
    for( let i=1; i<=20; i++ ){
        document.write(i);
        if(i == 10){
            break;
        }
    }
}

{
    let num =0;
    while(num < 10){
        num++;
        if(num == 5){
            continue;
        }
    document.write(num);

    }
    for(let i=1; i<= 10; i++){
        if( i == 5){
            continue;
        }
    document.write(i);
    }    
}