console 命令行工具 X clear
console
 
<!DOCTYPE html> 
<html> 
<head> 
<meta charset="UTF-8"> 
<title>九九乘法表</title> 
<script type="text/javascript"> 
document.write("<center><table border=\"3\">"); 
for (i = 1; i <= 9; i++) { 
    document.write("<tr>"); 
    for (j = 1; j <= 9; j++) { 
        if (j <= i) { 
            document.write("<td>" + i + "*" + j + "=" + i * j + "</td>") 
        } 
        else 
            document.write("<td>&nbsp;</td>"); 
    } 
    document.write("</tr>"); 
} 
document.write("</table></center>"); 
</script> 
</head> 
<body> 
</body> 
</html>