SOURCE

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

writeDocument("最大值最小值-------------------------")
writeDocument("最大值" + Math.max(1,3,8,10,18,9));
writeDocument("最小值" + Math.min(1,3,8,10,18,9));



writeDocument("生成4位随机验证码-------------------------")
function generateVerfyCode(length){
    var strLetterNumber = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    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(generateVerfyCode(4));
writeDocument(generateVerfyCode(5));
writeDocument(generateVerfyCode(6));



writeDocument("生成随机颜色 RGB(255,255,255)-------------------------")
function getColor() {
    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;
}

writeDocument(getColor());