Question

所以这是我关于代码的第一份家庭作业，过去的几个小时我一直在努力弄清楚这一点，但是我完全感到沮丧。

我试图通过输入三角形的三个边来查找三角形的区域（设法弄清楚了该怎么做），但是当我实际编译并运行代码时，.print无法正常工作

到目前为止，这是我的代码：

import java.util.Scanner;

// Purpose: To get the area of a triangle

public class ComputeTriangleArea  {

    // main method
    public static void main(String[] args) {

        // Creating a scanner
        Scanner scanner = new Scanner(System.in);

        //  Entering dimensions
        double x1 = scanner.nextDouble(); double y1 = scanner.nextDouble(); 
        double x2 = scanner.nextDouble(); double y2 = scanner.nextDouble(); 
        double x3 = scanner.nextDouble(); double y3 = scanner.nextDouble();

        // Inputting side 1
        System.out.print("Enter the dimensions of side 1: ");
        double side1 = Math.sqrt((x1-x2) * (x1-x2) + (y1-y2) * (y1-y2));

        // Inputting side 2
        System.out.print("Enter the dimensions of side 2: ");
        double side2 = Math.sqrt((x1-x3) * (x1-x3) + (y2-y3) * (y2-y3));

        // Inputting side 3
        System.out.print("Enter the dimensions of side 3: ");
        double side3 = Math.sqrt((x2-x3) * (x2-x3) + (y2-y3) * (y2-y3));

        // Convert to Area
        double s = (side1+side2+side3) / 2;
        double area = Math.sqrt(s * (s-side1) * (s-side2) * (s-side3));

        // Display the result
        System.out.printf("The area is %.2f\n", area);
    }
}

结果是，如果我输入1、2、3、4、5、6

它显示为：

java -cp。 ComputeTriangleArea

1

2

3

4

5

6

输入侧面1的尺寸，输入侧面2的尺寸，输入侧面3的尺寸，面积为3.87

退出代码：0

有人会介意以正确的方向指导我吗？

非常感谢您！

编辑：这是我在以下注释中从所有人的帮助下得到的代码：

import java.util.Scanner;

// Purpose: To get the area of a triangle

public class ComputeTriangleArea  {

// main method
public static void main(String[] args) {

// Creating a scanner
Scanner scanner = new Scanner(System.in);

// Inputting side 1
scanner = new Scanner(System.in);
System.out.print("Enter the dimensions of side 1: ");
double x1 = scanner.nextDouble();
double y1 = scanner.nextDouble();

// Inputting side 2
System.out.print("Enter the dimensions of side 2: ");
double x2 = scanner.nextDouble();
double y2 = scanner.nextDouble();

// Inputting side 3
System.out.print("Enter the dimensions of side 3: ");
double x3 = scanner.nextDouble();
double y3 = scanner.nextDouble();

double side1 = Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
double side2 = Math.sqrt((x1 - x3) * (x1 - x3) + (y1 - y3) * (y1 - y3));
double side3 = Math.sqrt((x2 - x3) * (x2 - x3) + (y2 - y3) * (y2 - y3));

// Convert to Area
double s = (side1 + side2 + side3) / 2;
double area = Math.sqrt(s * (s - side1) * (s - side2) * (s - side3));

// Display the result
System.out.printf("The area is %.2f\n", area);
    }
}

Answer 1

您可以尝试以下代码：

// main method
public static void main(String[] args) {

    // Creating a scanner
    Scanner scanner = new Scanner(System.in);

    // Inputting side 1
    System.out.print("Enter the dimensions of side 1: ");
    double x1 = scanner.nextDouble();
    double y1 = scanner.nextDouble();

    // Inputting side 2
    System.out.print("Enter the dimensions of side 2: ");
    double x2 = scanner.nextDouble();
    double y2 = scanner.nextDouble();

    // Inputting side 3
    System.out.print("Enter the dimensions of side 3: ");
    double x3 = scanner.nextDouble();
    double y3 = scanner.nextDouble();

    double side1 = Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
    double side2 = Math.sqrt((x1 - x3) * (x1 - x3) + (y2 - y3) * (y2 - y3));
    double side3 = Math.sqrt((x2 - x3) * (x2 - x3) + (y2 - y3) * (y2 - y3));

    // Convert to Area
    double s = (side1 + side2 + side3) / 2;
    double area = Math.sqrt(s * (s - side1) * (s - side2) * (s - side3));

    // Display the result
    System.out.printf("The area is %.2f\n", area);
}

已更新 使用单个Scanner而不是多个create Scanner，enter键不会破坏System.in（这是我以前的错误观点，认为enter键会破坏{ {1}}）

Answer 2

该输出是您编写的代码所期望的。我假设您希望输出为（请提供预期的输出）

Enter the dimensions of side 1: 1 2
Enter the dimensions of side 2: 3 4
Enter the dimensions of side 3: 5 6
The area is 3.87

如果您观察代码，则首先扫描了所有6个数字，然后打印语句。这样输出就如您所愿。

如果您希望输出如我所显示的那样，则需要打印每一面的对帐单，在每个打印对帐单后扫描2个数字。

Java：.print无法按照我在代码中的预期工作

2 个答案: