<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>水仙花数</title>
<script type="text/javascript">
for (var num =100;num <=999;num++){
var b =parseInt(num /100);
var s =parseInt(num %100 /10);
var g =num %100 %10;
if (Math.pow(b,3) +Math.pow(s,3) +Math.pow(g,3) ==num){
console.log(num)
}
}
</script>
s
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>while循环练习1</title>
<script type="text/javascript">
// 1、假如投资的年利率为5%，试求从1000块增长到5000块，需要花费多少年
// 1000 1000+10000.05=10001.05
// 1050 1050+10500.05=10501.05
// ……
// 5000
var money = 1000;
var count = 0;
while(money <= 5000){
money*=1.05;
count++;
}
console.log(count)
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>while练习2</title>
<script type="text/javascript">
/*
while循环重写小明的成绩，如果用户输入不合法就反复输入，直到正确为止
*/
while (true){
var score = prompt('请输入小明的成绩');
if (!+score || (+score*10%5 != 0) || +score>100 || +score<0) {
alert('非法输入');
}else {
break;
}
}
</script>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script type="text/javascript">
var sum=0;
for(var i=1;i<100;i+=2)
{
sum+=i;
}
document.write("100以内所有奇数和为："+sum);
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>水仙花数</title>
<script type="text/javascript">
for (var num =100;num <=999;num++){
var b =parseInt(num /100);
var s =parseInt(num %100 /10);
var g =num %100 %10;
if (Math.pow(b,3) +Math.pow(s,3) +Math.pow(g,3) ==num){
console.log(num)
}
}
</script>
s
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script type="text/javascript">
var num = prompt("请输入一个大于1的自然数:");
/*创建布尔值*/
var flag = true;
/*判断值是否合法*/
while(num<=1 || isNaN(num)){
alert("这个数不合法");
var num = prompt("请重新输入：");
}
for(var i = 2 ; i<num ; i++){
/*判断i是否能被j整除*/
if(num%i == 0){
/*判断进入i不是质数，改变布尔值*/
var flag = false;
break;
}
}
if(flag){
/*flag为true则输出*/
alert(num+"是质数");
}else{
alert("这个数不是质数");
}
</script>
</head>
<body>
</body>
</html>
