编写一个Java程序来显示一个三位数的百位、十位和个位的值

write a Java program to show the value of the hundreds place, the tens place, and the ones place for a three-digit number

提问by Wilyum

I am a noob to java and I need advice to fix this code, I need to write a Java program to show the value of the hundreds place, the tens place, and the ones place for a three-digit number. This is what I have so far, any ideas to how to get it to work? I'm not getting any errors, but my number isn't even outputting to the console correctly. Like if I typed in 123 for my 3 digit number everything prints blank. For example:

我是 Java 的菜鸟，我需要建议来修复此代码，我需要编写一个 Java 程序来显示三位数的百位、十位和个位的值。到目前为止，这就是我所拥有的，有关如何使其工作的任何想法？我没有收到任何错误，但我的号码甚至没有正确输出到控制台。就像我为我的 3 位数字输入 123 一样，所有内容都打印为空白。例如：

Enter a 3 digit number: 123 Hundreds place digit: Tens place digit: Ones place digit: Error! Number more then 3 digits. Error! Number less then 3 digits.

输入一个 3 位数字：123 百位数字：十位数字：个位数字：错误！数字超过 3 位。错误！数字少于 3 位。

It's not detecting my input of '123' for example, or anything else I put.

例如，它没有检测到我输入的“123”或我输入的任何其他内容。

    import java.util.Scanner;
        public class ValueOfDigits {
            public static void main(String[] args) {

                //Create new scanner
                Scanner input = new Scanner(System.in);

                //Values of each digit
                int hundreds = 0;
                int tens = 0;
                int ones = 0;

                //Prompt user to input 3 digit number           
                System.out.print("Enter a 3 digit number: ");
                int number = input.nextInt();

                //Displays hundreds place digit
                hundreds = number / 100;
                System.out.printf("Hundreds place digit: " , hundreds);

                //Displays tens digit
                tens = (number - hundreds) / 10;
                System.out.printf("\nTens place digit: " , tens);


                //Display ones digit
                ones = (number - tens - hundreds);
                System.out.printf("\nOnes place digit: " , ones);   


                //Error if number is less or more then three digits
                if (number > 999); 
                System.out.println("\nError! Number more then 3 digits.");
                if (number < 100);
                System.out.println("Error! Number less then 3 digits.");
}

}

}

采纳答案by sinclair

Replace System.out.printf("Hundreds place digit: " , hundreds);with System.out.println("Hundreds place digit: " + hundreds);and remove the ;after the if-statments.

替换System.out.printf("Hundreds place digit: " , hundreds);为System.out.println("Hundreds place digit: " + hundreds);并删除-statments;之后的if。

If you want to use printftake a look at this: https://docs.oracle.com/javase/7/docs/api/java/io/PrintStream.html#printf(java.lang.String,%20java.lang.Object...)

如果你想使用printf看看这个：https: //docs.oracle.com/javase/7/docs/api/java/io/PrintStream.html#printf(java.lang.String,%20java.lang.目的...）

回答by Shahid

You have little error of calculating tenth and ones digit.

您在计算第十位和个位时几乎没有错误。

           //Displays tens digit
            tens = (number %100) / 10;
            System.out.println("Tens place digit: " + tens);

            //Display ones digit
            ones = number %10;
            System.out.println("Ones place digit: " ,+ ones);

Remove semicolons after if conditions.

删除 if 条件后的分号。

Again, the 3 digit checking should be done just after reading the number. Otherwise pointless calculation will be done for invalid numbers.

同样，应在读取数字后立即进行 3 位数检查。否则对无效数字将进行无意义的计算。

回答by Peter Rahul

Completely Fixed code is here : You can compare with your code to find error in your code

完全固定的代码在这里：您可以与您的代码进行比较以查找代码中的错误

      import java.util.Scanner;
       class ValueOfDigits {
          public static void main(String[] args) 
           {
             //Create new scanner
            Scanner input = new Scanner(System.in);

            //Values of each digit
            int hundreds = 0;
            int tens = 0;
            int ones = 0;

            //Prompt user to input 3 digit number           
            System.out.print("Enter a 3 digit number: ");
            int number = input.nextInt();

  if (number <= 999 && number > 99)   // Checking condition for three digit number
  {

            //Displays hundreds place digit
            hundreds = number / 100;
            System.out.printf("Hundreds place digit: " + hundreds);

            //Displays tens digit
            tens = (number - (hundreds*100)) / 10;  // compare with your code
            System.out.printf("\nTens place digit: " + tens);


            //Display ones digit
            ones = (number - (tens*10) - (hundreds*100));   // compare with your code
            System.out.printf("\nOnes place digit: " + ones);   
  }
                             //Error if number is less or more then three digits
else                                                                    
{      
  if (number > 999)
            System.out.println("\nError! Number more then 3 digits.");
            if (number < 100)
            System.out.println("Error! Number less then 3 digits.");
  }



  }
  }

回答by Pooja

We can get ones, hundred or any other place value in Java using a simple code as shown below:

我们可以使用如下所示的简单代码在 Java 中获取 1、10 或任何其他位值：

int n=356;
int one=(n/1)%10;
int tens= (n/10)%10;
int hundred = (n/100)%10;

回答by Shakhobbek Juraev

'import java.util.Scanner;

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    if (a < 10) {
      System.out.println(0);
    } else {
      System.out.println((a- (a/100)*100)/10);
    }
  }
}'