<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
<script>
//将数组中的所有元素相加,求和
var arr=[12,56,89,12,0.5,4.9,18];
var n=0;
for(var i=0;i<arr.length;i++){
n+=arr[i]
}
console.log(n)
</script>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
<script>
//将数组中的所有元素相加,求和
var arr=[12,56,89,12,0.5,4.9,18];
var n=0;
for(var i=0;i<arr.length;i++){
n+=arr[i]
}
console.log(n)
</script>
</body>
</html>