Question

我的代码编译正确。当我运行我的程序时，输出要求我输入包的重量。如果我输入一个负数，程序会要求我再次输入重量，但不会停止让我输入另一个数字。

我认为问题出在＆＃34;而＃34;声明，但我不确定。

任何帮助都将不胜感激。

import java.util.Scanner;

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

    int weight, distance, distancex;
    double rate, price;
    rate = 0.00;

    System.out.print("Please enter package weight: ");
    weight = input.nextInt();


    while (weight <= 0 || weight >= 61)
    {
        System.out.print("Please enter package weight: ");
    }

    if (weight <= 10 && weight >= 1 )
    {
        rate = 5.01;
    }
    else if ( weight <= 20 && weight >= 11 )
    {
        rate = 7.02;
    }
    else if ( weight <= 30 && weight >= 21 )
    {
        rate = 9.03;
    }
    else if ( weight <= 40 && weight >= 31 )
    {
        rate = 11.04;
    }
    else if ( weight <= 60 && weight >= 41)
    {
        rate = 15.00;
    }

 System.out.print("Please enter distance: ");
    distance = input.nextInt();

    while ( distance <= 0 )
        {
            System.out.print("Please enter distance: ");
        }

    distancex = ( distance / 100 ) + 1;
    price = ( distancex * rate );

    System.out.printf("Your total shipping cost for %d miles is $%.2f\n", distance, price);
    }
}

Answer 1

您需要让用户在while循环内再次输入重量。

while (weight <= 0 || weight >= 61) {
    System.out.print("Please enter package weight: ");
    weight = input.nextInt();
}

你也可以使用do-while循环：

do {
    System.out.print("Please enter package weight: ");
    weight = input.nextInt();
} while (weight <= 0 || weight >= 61);

如果你使用do-while循环，你可以在第一次询问和while循环时删除。这是一种稍微紧凑的方式。

java while语句的问题？

1 个答案: