js determined if + switch break cycles, while + do while loop

if else circulation

var NUM = prompt ( " Enter a number: " ); behind else not increase determination condition, else the final output in a multi-condition
     IF (NUM> = 80 && NUM <= 100 ) 
        { 
            Alert ( " you learn good, Come on! " );     
        } 
    the else  IF (NUM> = 60 && NUM < 80 ) 
        { 
        Alert ( " good " ); 
        } 
    the else  IF (NUM> = 50 && NUM < 60 ) 
        { 
            Alert ( "It is almost, come on . "); 
        } 
    The else  IF (NUM> 0 && < 50 ) {
         the else ( " hard efforts, do not be lazy " ); 
    } 
    the else { 
        Alert ( " Your input is wrong " ); 
    }
    

<Script type = " text / JavaScript " >
     / * user to input 1-7, judgment of the week * / 
    var NUM = prompt ( " Please enter a number between 1-7: " ); and if the difference, switch only can write the value
     / * the string to type int * / 
    NUM = the parseInt (NUM);
     Switch (NUM) {
     Case  . 1 :   
        Alert ( " Monday " );
         BREAK ;
     Case  2 : 
        Alert ( " Tuesday " );
         BREAK ;
     Case  3 :
        Alert ( " Wednesday " );
         BREAK ;
     Case  4 : 
        Alert ( " Thursday " );
         BREAK ;
     Case  5 : 
        Alert ( " Friday " );
         BREAK ;
     Case  6 : 
        Alert ( " Saturday " );
         BREAK ;
     Case  7 : 
        Alert ( " seven weeks " );
         BREAK ;
        default : 
            Alert ( " you entered incorrectly, please re-enter " );
             break ; 
    } 
    let the user inputs 1 - . 7 , if the displayed work day 1-5, if 6- seven days rest in display termination determination using a break, will be omitted Analyzing intermediate

var num2 = prompt ( " Please enter the date " ); 
    num2 = the parseInt (num2);
     Switch (num2) {
         Case  . 1 : 
        
        Case  2 : 
            
        Case  . 3 : 
            
        Case  . 4 : 
            
        Case  . 5 : 
            Alert ( " days " );
             BREAK ;
         Case  6 : 
            
        Case  7 : 
            Alert ( " day of rest " );
             bREAK ;
         default :
            Alert ( " please re-enter " );
             BREAK ; 
            
    }
 </ Script>

do while performing the first determination

Circulation print array

var i=1；
do{alert（i，i++）};
while(i<=4);