小编v_7*_*v_7的帖子

String car; 

    if (type == 'E')
        {fee = rate*50;
         car = "Economy";}

    else if (type == 'M')
         {fee = rate*70;
         car = "Midsize";}


    else if (type == 'F')
        {fee = rate*100;
        car = "Fullsize";}

System.out.println("Car type is " + car);

这是我遇到问题的程序的一部分.我得到'本地变量车可能尚未初始化'.我应该怎么做才能让'汽车'初始化？

public class Interest {
    public static void main(String[] args) {
        int n;          // number of years
        double rate;    // annual rate

        for (int r = 5; r<=10; r++ ) {
            System.out.println("\nInterest rate is  " + r + "%");
            System.out.println("**********************");
            System.out.println("Year\tAmount on deposit");

            for (n=1; n<=10; n++) {
                int p = 1000; // original amount
                rate = r / 100;
                double a = p * (Math.pow(1 + rate, n)); // amount on deposit at the end of year
                System.out.printf("\n%d\t%.2f", n, a); …

我有一个家庭作业,我应该写几个方法(例如,提示客户的汽车类型并返回有效的汽车类型的方法)然后我的程序应显示汽车类型,汽车租用的天数,额外这是老师要我写的第一种方法,

public static String promptForCarType(){
        Scanner input = new Scanner(System.in);
        char type;
        System.out.println("(E) Economy  - 50 TL");
        System.out.println("(M) Midsize  - 70 TL");
        System.out.println("(F) Fullsize - 100 TL");
        do{
            System.out.println("Enter the car type (E/M/F) : ");
            type = input.next().charAt(0);
            type = Character.toUpperCase(type);
        } while (type != 'E' && type != 'M' && type != 'F' ); //I tried to define condition with "||" operator,didn't work.


        switch(type) {
            case 'E' : ;return "Economy";             
            case 'M' : return "Midsize";
            case 'F' : return …