问题描述
我正在尝试编写一个程序,提示用户输入酒店的楼层总数、每层楼的房间数以及已入住的房间数.最后,它应该显示房间总数、已占用房间总数和已占用房间百分比.我在显示已占用房间的百分比时遇到问题.我正在使用所有 int 数字.
I'm trying to write a program that prompts the user to enter the total amount of floors in a hotel, the number of rooms in each floor, and the number of occupied rooms. In the end it should display the total # of rooms, the total # of rooms occupied, and the percentage of the rooms occupied. I am having problems with displaying the percentage of rooms occupied. I'm using all int numbers.
这是我提出的等式:
roomsOccPercentage = (totalRoomsOccupied * 100) / totalRooms ;
当我将程序提交到教授的 Java 运行器时,它显示:
When I submit the program into my professor's Java runner it displays:
65 % of the Rooms are occupied.
但是我的教授提供的答案输出了 66%,因此程序不会接受我的文件.
But the one my professor provided outputted the answer 66 % instead so the program won't accept my file.
有谁知道我做错了什么?是 DecimalFormat 错误吗?
Does anyone know what I'm doing wrong? Is it a DecimalFormat error?
这是整个代码
import java.util.Scanner;
import java.text.DecimalFormat;
public class hw7_1 {
public static void main(String[]args) {
Scanner keyboard = new Scanner(System.in);
DecimalFormat formatter = new DecimalFormat("#0");
int totalFloors;
int totalRooms = 0;
int numFloors;
int numRooms;
int roomsOccupied;
int totalRoomsOccupied = 0;
int roomsOccPercentage = 0;
//prompting users to input # of floors, no inputs below 1 floor
do {
System.out.println("Please enter the number of floors in the hotel: ");
numFloors = keyboard.nextInt();
if (numFloors < 1) {
System.out.println("You have entered an invalid number of floors. ");
}
}
while (numFloors < 1);
//for loops on how many rooms on each hotel floors
for ( int Floors = 1; Floors <= numFloors; Floors++) {
if (Floors == 13 ) {
continue;
}
do {
System.out.println("Please enter the number of rooms on floor #: " + Floors );
numRooms = keyboard.nextInt();
if (numRooms < 10) {
System.out.println("You have entered an invalid number of rooms. ");
}
} while (numRooms < 10);
System.out.println("Please enter the number of occupied rooms on floor #: " + Floors);
roomsOccupied = keyboard.nextInt();
totalRooms = totalRooms + numRooms;
totalRoomsOccupied = totalRoomsOccupied + roomsOccupied;
roomsOccPercentage = (totalRoomsOccupied * 100) / totalRooms ;
}
System.out.println("\nThe hotel has a total of " + totalRooms + " rooms.");
System.out.println(totalRoomsOccupied + " of the rooms are occupied.");
System.out.println(formatter.format(roomsOccPercentage) + "% of the rooms are occupied.");
}
}
推荐答案
您需要先将 roomsOccPercentage
设为双倍.
You need to make your roomsOccPercentage
a double first.
double roomsOccPercentage = 0.0;
然后转换任一操作数以避免整数除法.
and then cast either of the operands so avoid an integer division.
roomsOccPercentage = (totalRoomsOccupied * 100.0) / totalRooms;
您可以使用像 (double)totalRoomsOccupied
这样的显式转换,也可以将 100
设为 100.0
,这是一个浮点数,因此也进行除法,浮点除法而不是整数除法.
You can either use an explicit cast like (double)totalRoomsOccupied
or just make 100
as 100.0
which is a floating point number, thus making the division too, a floating point one and not an integer division.
这篇关于Java:整数除法向上取整的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!