用JavaScript实现100以内自然数求和
2015-03-2419:51:46
//第一种方法：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="Generator" content="EditPlus®">
<meta name="Author" content="">
<meta name="Keywords" content="">
<meta name="Description" content="">
<title>实现100以内自然数求和</title>
</head>
<script language='javascript'>
//实现100以内自然数求和，网页预览效果如图
var i=1,sum=0; //声明变量i和sum;
while(i<=100){
sum+=i;i++
}
document.write('1+2+3+...+100='+sum);//向页面中输入结果
</script>
<body>
</body>
</html>
//第二种方法：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="Generator" content="EditPlus®">
<meta name="Author" content="">
<meta name="Keywords" content="">
<meta name="Description" content="">
<title>100以内自然数求和</title>
</head>
<script>
var sum=0;
for(var i=1;i<=100;i++){
sum+=i;
}
document.write('1+2+3+...+100='+sum);
</script>
<body>
</body>
</html>
//第三种方法：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="Generator" content="EditPlus®">
<meta name="Author" content="">
<meta name="Keywords" content="">
<meta name="Description" content="">
<title>100以内自然数求和</title>
<script>
var i=1,sum=0;
do{
sum+=i;
i++
}
while(i<=100){
document.write('1+2+3+...+100='+sum);
}
</script>
</head>
<body>
</body>
</html>
个人喜好比较喜欢用for循环，感觉for的逻辑比较符合思维方式
