1. <!DOCTYPE html>
    2. <html lang="en">
    3. <head>
    4.     <meta charset="UTF-8">
    5.     <title>4-1Math-ceil练习</title>
    7.     <script type="text/javascript">
    9.         //带小数的数，都取最大整数(向上舍取)
    10.         alert("正数：" +Math.ceil(25.5));
    11.         alert("负数：" +Math.ceil(-25.5));
    13.     </script>
    15. </head>
    16. <body>
    18. </body>
    19. </html>