2
<script>
    function  order(a,b,c){
        var sum;
        var str;
        if(a>b){
            sum=a;
            a=b;
            b=sum;
        }
        if(b>c){
            sum=b;
            b=c;
            c=sum;
        }
          if(a>b) {
              sum = a ;
              a = b ;
              b = sum ;
          }
            str= a+"<"+b+"<"+c;
        document.write(str);

    }
    order(5,0,4);
</script>
3
<script>
    function rand() {
        for(i=0;i<4;i++) {
            document.write(parseInt(Math.random() * 10));
        }
        document.write("<br>")
    }
    function start() {
        for(var i=1;i<11;i++ ){
            rand();
        }
    }
    start();

</script>
4
<script>

        var row=Number(prompt("请输入行数"));
        var col=Number(prompt("请输入列数"));

    function start() {
        row,col;
       var  str="<table>";
        for(var j=0;j<row;j++){
            str+="<tr>";
            for(var i=0;i<col;i++){
                str+="<td></td>";
            }
            str+="</tr>";
        }
        str+="</table>";
        document.write(str);
    }
 start();
</script>
5


var sum = 0;
    var attr = [12,34,2,5,76];
    for(var i = 0;i < attr.length;i++){
        sum = sum + attr[i];
    }alert(sum);

6
var attr = [];
    for(var i = 0;i < 10;i++){
        attr[i] = parseInt(Math.random()*90+10);
    }
    var attr = [69,54,95,47,88,17,42,93,85,67];
    for(var j = 0;j < attr.length-1;j++){
        for(var k = j+1;k < attr.length;k++){
            if(attr[j] > attr[k]){
                var zhong = attr[j];
                attr[j] = attr[k];
                attr[k] = zhong;
            }
        }
    }
     console.log(attr);
     var b = [69,54,95,47,88,17,42,93,85,67];
     for(j = 0;j<b.length;j++){
         for(k = 0;k < b.length-1-j;k++){
             if(b[k] > b[k+1]){
                 var temp = b[k];
                 b[k] = b[k+1];
                 b[k+1] = temp;
             }
         }
     }

7
var arr=[1,2,3,4];   //定义数组的值
function map(arr){    //定义一个函数Map（arr）
    for(var i=0;i<arr.length;i++){  //定义变量i，
       arr[i]=arr[i]*(i+0.3)         //在原数组的基础上加30%
    }
   return arr;                    //返回数组重新循环，直到条件不符合
}
console.log(map(arr));         //打印曾加后的数组



8
var x = shiJian();
    function shiJian(){
        var mydate = new Date();
        var y = mydate.getFullYear();
        //提取月份:提取的数值 +1即为当前的月份
        var m = mydate.getMonth();
        //提取日期
        var d = mydate.getDate();
        //提取当前时间：几时几分与上下午
        var h = mydate.getHours();
        var fen = mydate.getMinutes();
        var s = mydate.getSeconds();
        var z = y + "-" + (m + 1) + "-" + d + " " + h + ":" + fen + ":" + s;
        alert(z);

9
var shuzu = [1,5,4,4,7,6,6];
quchong(shuzu);
function quchong(shuzu){
    var attr=[];
     for(var i =0;i<shuzu.length;i++){
        if(attr.indexOf(shuzu[i]) < 0){
         attr.push(shuzu[i]);
        }
    }document.write(attr);
    
}
        return z; 
    }