SOURCE

function writeDocument(variable){
    document.write(variable + "<br/>");
}

writeDocument("最大值最小值-------------")
writeDocument("最大值："+Math.max(1,3,9,19,999));
writeDocument("最小值："+Math.min(1,3,9,19,999));

writeDocument("生成随机验证码---------------------")

function generateVerifyCode(length){
    var strLetterNumber = "0123456789ABCDEFGHIJKLMNOPQRST";
    var code = "";
    for(var i=0;i<length;++i){
        var randomNumber =Math.floor(Math.random()*strLetterNumber.length);
        code = code+strLetterNumber.charAt(randomNumber);
    }
    return code;
}

writeDocument(generateVerifyCode(4));
writeDocument(generateVerifyCode(5));
writeDocument(generateVerifyCode(6));

writeDocument("生成随机的颜色 rgb(255,255,255)-------------------")
function getRandomColor(){
    var r=Math.floor(Math.random()*(255+1));
    var g=Math.floor(Math.random()*(255+1));
    var b=Math.floor(Math.random()*(255+1));
    var rgb="rgb("+r+","+g+","+b+")";
    return rgb;
}
document.write(getRandomColor());