SOURCE

console 命令行工具 X clear

                    
>
console
function writeDocument(variable){
    document.write(variable+"<br/>");
}
writeDocument("for循环------------------------");
var sum=0;
for(var i=1;i<101;i++){
    
    sum+=i;
}
writeDocument(sum);
writeDocument("whlie循环------------------------");
var a=1;
var sum1=0;
while(a!=101){     
   sum1+=a;
    a++;  
}
writeDocument(sum1);
writeDocument("do...whlie循环------------------------");
var b=1;
var sum2=0;
do{
    sum2+=b;
    b++;
}while(b!=101)
writeDocument(sum2);
<!DOCTYPE html> 
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
    <script>
    </script>
</head>
<body>
</body>
</html>