20190326-js基础2_作业

实例  for循环打印九九乘法表

        for(i=1;i<=9;i++){
            for(j=1;j<=i;j++){
                document.write(j+'*'+i+'='+i*j+' ');
            }
            document.write('<br/>');
        }

实例 用while循环打印出一个三角形

var i=1;
        while(i<20){
            var j=1;
            document.write("<div style='text-align:center'>");

            while(j<=i){
                document.write('*');
                j++;
            }

            document.write('</div>');
            i++;
        }