java - 初学者 Java - 找不到符号错误？

Question

我一直在试图找出为什么这个基本的 java 程序无法运行。我收到大约 7 个找不到符号错误。任何帮助将非常感激。我很想知道我做错了什么。

该程序只是一些基本计算，提示一些输入和输出数据，显示超速者的罚款金额。

import java.io.*;
import java.util.*;

public class Lab1 {
public static void main (String args[]) {

    // Create a scanner to read from keyboard
    Scanner kbd = new Scanner(System.in);

    System.out.print("\nEnter Driver's FIRST Name.");
    String firstName = kbd.next();

    System.out.print("\nEnter Driver's LAST Name.");
    String lastName = kbd.next();

    System.out.print("\nEnter Driver's Age.");
    int age = Integer.parseInt(kbd.next());

    System.out.print("\nEnter the Speed Limit.");
    int speedLimit = Integer.parseInt(kbd.next());

    System.out.print("\nEnter Driver's Actual Speed");
    int actualSpeed = Integer.parseInt(kbd.next());

    System.out.print("\nDid violation occur in construction zone? (yes/no)");
    String constructionZone = kbd.next();

    int speedDifference = (actualSpeed - speedLimit);



    if (speedDifference <= 5) {
        int baseFine = 0;
    }
    else if(speedDifference >= 20) {
        int baseFine = (speedDifference / 5) * 50;
    }
    else {
        int baseFine = (speedDifference / 5) * 30;
    }



    if(constructionZone.equals("yes")) {
        int constructionFine = 10;
    }
    else {
        int constructionFine = 0;
    }



    if(age <= 21 && speedDifference >= 20) {
        int underageFine = 300;
    }
    else {
        int underageFine = 0;
    }



    int totalFine = baseFine + constructionFine + underageFine;

    System.out.println("Last Name: " + lastName);
    System.out.println("First Name: " + firstName);
    System.out.println("Driver Age: " + age);
    System.out.println("Speed Limit: " + speedLimit);
    System.out.println("Actual Speed: " + actualSpeed);
    System.out.println("MPH Over Limit: " + speedDifference);
    System.out.println("Base Fine: $" + baseFine);
    System.out.println("Construction Zone Fine: $" + constructionFine);
    System.out.println("Underage Fine: $" + underageFine);
    System.out.println("Total Fine: $" + totalFine);

}
}

Answer 1

您的变量 baseFine、constructionFine 和 underageFine 是在 if 语句的范围内定义的。将它们声明在该范围之外，以便它们在 main 方法的范围内可见。例如

int baseFine = 0;
if (speedDifference <= 5) {
     baseFine = 0;
}