Java 我将如何使用 while 循环来不断请求用户输入
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How would I use a while loop to keep requesting user input
提问by Imminence
I've tried a couple of things with the while loop and can't seem to get it to work. I want to keep requesting user input until the user inputs the number 0, here is the code I have so far:
我已经用 while 循环尝试了几件事，但似乎无法让它工作。我想一直请求用户输入，直到用户输入数字 0，这是我到目前为止的代码：
import java.util.*;
public class Task10 {
public static void main(String[] args) {
System.out.println("Enter a year to check if it is a leap year");
Scanner input = new Scanner(System.in);
int year = input.nextInt();
if ((year % 4 == 0) || ((year % 400 == 0) && (year % 100 != 0)))
System.out.println(year + " is a leap year");
else
System.out.println(year + " is not a leap year");
}
}
采纳答案by vish4071
Use a while loop above input line as:
在输入行上方使用 while 循环作为：
while(true)
And, use ifcondition to break.
并且，使用if条件到break.
if(year == 0)
break;
Also, condition for leap yearis wrong in your code. It should be:
此外，leap year您的代码中的条件错误。它应该是：
if((year % 100 == 0 && year % 400 == 0) || (year % 4 == 0 && year % 100 != 0))
//its a leap year
else
//its not
PS: As in comments, I'll give a complete code:
PS：在评论中，我会给出一个完整的代码：
import java.util.*;
public class Task10 {
public static void main(String[] args) {
System.out.println("Enter a year to check if it is a leap year");
while(true){
Scanner input = new Scanner(System.in);
int year = input.nextInt();
if(year == 0)
break;
if((year % 100 == 0 && year % 400 == 0) || (year % 4 == 0 && year % 100 != 0))
System.out.println(year + " is a leap year");
else
System.out.println(year + " is not a leap year");
}
}
}
回答by NightsWatch
You should place your input taking code inside a while loop aned execute while loop untill year is 0 or lesser.
你应该把你的输入代码放在一个 while 循环中，然后执行 while 循环，直到 year 为 0 或更小。
public static void main(String[] args) {
int year = 1;
while(year > 0)
{
System.out.println("Enter a year to check if it is a leap year");
Scanner input = new Scanner(System.in);
year = input.nextInt();
if ((year % 4 == 0) || ((year % 400 == 0) && (year % 100 != 0)))
System.out.println(year + " is a leap year");
else
System.out.println(year + " is not a leap year");
}
}
回答by Saif Asif
You need to do something to keep you input loop running until a stopping condition is encountered (which in your case is that when the user inputs 0)
您需要做一些事情来保持输入循环运行，直到遇到停止条件（在您的情况下是用户输入时0）
// First get the scanner object with the input stream
Scanner sc = new Scanner(System.in);
// Just using do-while here for no reason, you can use a simple while(true) as well
do{
int input = sc.nextInt(); // read the next input
if (int == 0) { // check if we need to exit out
// break only if 0 is entered, this means we don't want to run the loop anymore
break;
} else {
// otherwise, do something with the input
}
} while(true); // and keep repeating
