Question

我在这行“System.out.println（（num1 / dem1）（num2 / dem2））”中收到错误;“

错误说：

此行有多个标记 - 作业的左侧必须是变量 - 令牌“）”上的语法错误，AssignmentOperator之后的预期这个标记

package project;
import java.util.Scanner;

 public class summerproject {
 public static void main(String[] args)  
    {
     Scanner in = new Scanner( System.in );
     {
    //INPUT NUMBERS
     System.out.println("Enter Numerator 1. ");
     int num1 = in.nextInt(); 
     System.out.println("Enter Denominator 1. ");
     int dem1 = in.nextInt();
     System.out.println("Enter Numerator 2. ");
     int num2 = in.nextInt();
     System.out.println("Enter Denominator 2. ");
     int den2 = in.nextInt();
     }
     System.out.println("Press 1 to multiply");
     int mult = in.nextInt();


     if (mult == 1)
     {
         System.out.println((num1/dem1)(num2/dem2));   
     }
    }//ARGS BRACKET      
 }//END BRACKET

Answer 1

此行无效：

System.out.println((num1/dem1)(num2/dem2));

(num1/dem1)和(num2/dem2)需要在它们之间设置运算符。例如，要将两个表达式相乘，请使用*运算符：

(num1/dem1)*(num2/dem2)

Java的行为与数学不同，串联意味着乘法。相反，您必须明确地将操作数相乘。

此外，您宣布了

int den2 = in.nextInt();

这应该是

int dem2 = in.nextInt().

在适当调整大括号并进行上述修正后，您最终应该：

public class summerproject {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        //INPUT NUMBERS
        System.out.println("Enter Numerator 1. ");
        int num1 = in.nextInt();
        System.out.println("Enter Denominator 1. ");
        int dem1 = in.nextInt();
        System.out.println("Enter Numerator 2. ");
        int num2 = in.nextInt();
        System.out.println("Enter Denominator 2. ");
        int dem2 = in.nextInt();

        System.out.println("Press 1 to multiply");
        int mult = in.nextInt();

        if (mult == 1) {
            System.out.println((num1 / dem1) * (num2 / dem2));
        }
    }
}

示例运行：

Enter Numerator 1. 
20
Enter Denominator 1. 
4
Enter Numerator 2. 
30
Enter Denominator 2. 
5
Press 1 to multiply
1
30

Answer 2

您需要在操作过程中使用操作员

您的代码似乎表明您想要成倍增加，因此请尝试下面的代码......

System.out.println((num1/dem1)*(num2/dem2));

为什么这是一个错误？

2 个答案: