我刚刚写了一个很小的方法来计算手机短信的页数。我没有选择使用Math.ceil
进行四舍五入,老实说,它看起来非常丑陋。
下面是我的代码:
public class Main {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
String message = "today we stumbled upon a huge performance leak while optimizing a raycasting algorithm. Much to our surprise, the Math.floor() method took almost half of the calculation time: 3 floor operations took the same amount of time as one trilinear interpolation. Since we could not belive that the floor-method could produce such a enourmous overhead, we wrote a small test program that reproduce";
System.out.printf("COunt is %d ",(int)messagePageCount(message));
}
public static double messagePageCount(String message){
if(message.trim().isEmpty() || message.trim().length() == 0){
return 0;
} else{
if(message.length() <= 160){
return 1;
} else {
return Math.ceil((double)message.length()/153);
}
}
}
我真的不喜欢这段代码,我正在寻找一种更优雅的方式来做这件事。有了这个,我希望是3,而不是3.0000000。有什么想法吗?
发布于 2011-09-16 23:09:50
要向上舍入整数除法,您可以使用
import static java.lang.Math.abs;
public static long roundUp(long num, long divisor) {
int sign = (num > 0 ? 1 : -1) * (divisor > 0 ? 1 : -1);
return sign * (abs(num) + abs(divisor) - 1) / abs(divisor);
}
或者如果两个数字都是正数
public static long roundUp(long num, long divisor) {
return (num + divisor - 1) / divisor;
}
发布于 2013-11-20 16:00:36
另一个不太复杂的一行代码:
private int countNumberOfPages(int numberOfObjects, int pageSize) {
return numberOfObjects / pageSize + (numberOfObjects % pageSize == 0 ? 0 : 1);
}
可以使用long而不是int;只需更改参数类型和返回类型。
发布于 2017-01-25 02:39:32
谷歌的芭乐图书馆handles this in the IntMath class
IntMath.divide(numerator, divisor, RoundingMode.CEILING);
与这里的许多答案不同,它处理负数。当尝试除以零时,它也会抛出适当的异常。
https://stackoverflow.com/questions/7446710
复制相似问题