嘿,我一直有這個代碼的問題,因爲它沒有循環,當我輸入一個字符串重複的值。我無法理解我做錯了什麼。while語句循環錯誤
import java.util.Scanner;
public class MpgCalculator
{
public static void main(String[]args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Welcome to the MPG and CPM Calculator!");
double startOd, endOd, gallons, cost, mpg, cpm;
String repeat = "yes";
while(repeat.equals("yes")||repeat.equals("Yes")||repeat.equals("y")||repeat.equals("Y"))
{
System.out.println("Please Enter:");
System.out.print("\tYour Starting Odometer Reading: ");
startOd = sc.nextDouble();
System.out.print("\tYour Ending Odometer Reading: ");
endOd = sc.nextDouble();
System.out.print("\tThe Amount of Gallons Used: ");
gallons = sc.nextDouble();
System.out.print("\tThe Cost-per-Gallon That You Spent: ");
cost = sc.nextDouble();
mpg = getMpg(startOd, endOd, gallons);
cpm = getCpm(mpg, cost);
System.out.println("\nYour Miles-per-Gallon is " + mpg + ".");
System.out.println("Your Cost-per-Mile is " + cpm + ".");
System.out.print("Do it again? ");
repeat = sc.nextLine();
}
}
public static double getMpg(double startOd, double endOd, double gallons)
{
double mpg;
mpg = (endOd - startOd)/gallons;
return mpg;
}
public static double getCpm(double mpg, double cost)
{
double cpm;
cpm = cost/mpg;
return cpm;
}
}
在你的while語句中加上一個斷點,看看他'重複'的價值是什麼。 – DSway