交换积分顺序的诀窍在数形结合: 1. 几句顺口溜 后积先定限,限内穿条线,先交下限写,后交上限见 先积 x,画横线(平行于 x 轴),右减左: 先积 y,画竖线(平行于 y 轴),上减下: 2. 简单举例 Examples of changing the order of integration in double integrals ∫10∫ey1f(x,y)dxdy. 交换之后,先积 y 划竖线,上减下,则有: ∫e1{∫1lnxf(x,y)dy}dx
5.8 A monochrome screen is stored as a single array of bytes, allowing eight consecutive pixels to be stored in one byte.The screen has width w, where w is divisible by 8 (that is, no byte will be split across rows).The height of the screen, of cours
画8 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 3153 Accepted Submission(s): 1395 Problem Description 谁画8画的好,画的快,今后就发的快,学业发达,事业发达,祝大家发,发,发. Input 输入的第一行为一个整数N,表示后面有N组数据. 每组数据中有一个字符和一个整数
当我们在XCode中写程序时会不断的出现相关API提示窗体,那敲起来是一个爽啊. 有时候会看到一些API已经弃用了被画上红色的横线.说明该接口已经被弃用,仍保留,但不建议使用,对弃用API实现画横线事实上非常easy,仅仅须要在接口文件(.h)中这样写就可以实现上图效果,非常easy吧. /*! DEPRECATED: Use the [CustomIOS7AlertView init] method without passing a parent view. */ - (id)initWit