console 命令行工具 X clear

console

var g1=1;

function text1(){
    var j1=2;
    document.write(g1+"</br>");
}

var j3=3;

function text2(){
    var j4=4;
    document.write(j3+"</br>");
}
text1();
text2();
//
function Sum(a,b){
    return a+b;
}

var sum=100+Sum(2,3);

document.write(sum+"</br>");

function callAlert(){
    document.write("hallo");
}

function Pd(year){
    if(year>0){
        if(year%400==0||(year%4==0&&year%100!=0)){
        document.write("闰年"+"</br>");
    }
    else{
        document.write("不是闰年"+"</br>");
    }
}
    else{
        document.write("没有这个年份"+"</br>");
    }

}

Pd(2022);
Pd(2000);
Pd(-2);

//四个数求最大值
function Max(a,b,c,d){
    var arr=new Array(a,b,c,d);
    var max=arr[0];
    for(var i=1;i<arr.length;i++){
        if(max<arr[i]){
            max=arr[i];
        }
    }
    return max;
}

var a=Max(12,321,332,0);
document.write("最大值为"+a+"</br>");

<!DOCTYPE html> 
<html>
<head>
<meta charset="utf-8" />
<title></title>
<link rel="stylesheet" type="text/css" href="index.css"/>
<script src="js/index.js"></script>
</head>
<body>
<button onclick="callAlert()">调用</button>
</html>
</body>