SOURCE

var a=2;
var b=3;

var sum1=a<b;
if(sum1){
    document.write("2<3是真");
}
document.write('<br/>----------<br/>');

if(sum1){
    document.write("2<3是真");
}
else document.write("3");

document.write('<br/>----------<br/>');


var sum1=a>b;
if(sum1){
    document.write("2");
}
else if(3>1)document.write("3>1是真"+"<br/>");

function isInteger(num){
    var result = false;
    //判断是否是整数
    if(parseFloat(num)==parseInt(num)){ var result = true;}
    return result;
}
if (isInteger(15.9)){
    document.write("15 is an integer."+"<br/>");

}else{document.write("15 is not an integer."+"<br/>");}

function findDaffodilNum(){
    for(var num=100;num<999;num ++){
    var unitsDigit = num % 10;
    var tensDigit = parseInt((num/10)%10);
    var hundredsDigit = parseInt(num/100);
    var sum=unitsDigit*unitsDigit*unitsDigit+tensDigit*tensDigit*tensDigit+hundredsDigit*hundredsDigit*hundredsDigit;

if(num==sum)
{document.write("Print findDaffodilNum"+num+"<br/>");}
    }
}findDaffodilNum();


function isdecimalNum(num){
    var result = false;
    if(parseFloat(num)==parseInt(num)){ var result = true;}
    return result;
}
if (isdecimalNum(15.9)){
    document.write(" 15.9 is not an decimalNum."+"<br/>");

}else{document.write(" 15.9 is an decimalNum."+"<br/>");}