1.打印1-100之間所有奇數(shù)之和
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script>
var sum=0;
for(var i=0;i<=100;i++){
if(i%2!=0){
sum+=i
}
}
alert(sum)
</script>
</head>
<body>
</body>
</html>
123.png
2.打印1-100之間所有7的倍數(shù)的個(gè)數(shù)及總和
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script>
var sum=0;
var list=[];
for(var i=0;i<=100;i++){
if(i%7==0){
list.push(i)
sum+=i
}
}
alert(sum);
alert(list.length);
</script>
</head>
<body>
</body>
</html>
QQ圖片20180918093131.png
QQ圖片20180918093140.png
3.水仙花數(shù)是指一個(gè)3位數(shù)诗力，它的每個(gè)位上的數(shù)字的3 次冪之和等于它本身苇本。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script>
/*var a,b,c ;*/
for(i=100;i<1000;i++){
var a = parseInt(i%10);
var b = parseInt((i/10)%10);
var c = parseInt(i/100);
if(a*a*a+b*b*b+c*c*c== i){
alert(i +"是水仙花數(shù)");
}
}
</script>
</head>
<body>
</body>
</html>
水仙花.png
4.在頁(yè)面中接收一個(gè)用戶輸入的數(shù)字笛厦，并判斷該數(shù)是否是質(zhì)數(shù)裳凸。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script>
var num=parseInt(prompt("用戶輸入的數(shù)字"))
for (var i = 2; i < num; i++) {
if (num%i==0){
alert("不是質(zhì)數(shù)");
break;
}else{
alert("是質(zhì)數(shù)");
break;
}
}
</script>
</head>
<body>
</body>
</html>
5.打印出1-100之間所有的質(zhì)數(shù)
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script>
for(i=2; i<=100; i++){
for(var j=2 ; j<i ; j++){
if(i%j == 0){
document.write(i+"<br/>");
break;
}
}
}
</script>
</head>
<body>
</body>
</html>
Document.png
6.打印99乘法表
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script>
for(i=1;i<=9;i++){
for(j=1;j<=9;j++){
document.write (i+"*"+j+"="+i*j+"  ");
if(i==j){
document.write ("<br/>");
break;
}
}
}
</script>
</head>
<body>
</body>
</html>
99.png
