SOURCE

function writeDocument(variable) {
    document.write(variable + "<br/>");
}
writeDocument("生成随机验证码---------------");

function generateVerifyCode(length){
    var strValue="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    var code="";

    for(var i=0;i<length;++i){
        var randomIndex=Math.floor(Math.random()*strValue.length);
        code+=strValue.charAt(randomIndex);
    }
    return code;
}
writeDocument(generateVerifyCode(4));
writeDocument(generateVerifyCode(5));
writeDocument(generateVerifyCode(6));

writeDocument("用Math的方法找出3, 9, 12, 99, 45, 78中的最大值和最小值-------------");
writeDocument("最大值："+Math.max(3,9,12,99,45,78));
writeDocument("最小值："+Math.min(3,9,12,99,45,78));

writeDocument("请写一个随机生成颜色值rgb(X, Y, Z)的函数,其中X，Y，Z表示的是0~255的数字---"); 
function rgb(length){
    var code="";

    for(var i=0;i<length;++i){
        var a=Math.floor(Math.random()*256);
        code=a;
    }
    return code;
}
writeDocument(rgb(3));