Question

我必须写一个do循环来读取整数并计算它们的总和。连续两次读取零或相同值时停止。例如，如果输入为1 2 3 4 4，则总和为14并且循环停止。如果用户输入为0，我也需要知道是否可以为do while语句使用多个参数，或者如果我需要在stamenent中嵌套另一个参数。

    int input = 0;
    int total = 0;
    int update = 0;

    System.out.println("Enter any number");
    total = inputDevice.nextInt();

    do
    {
        System.out.println("Enter any number");
        input = inputDevice.nextInt();

        // Do i have to nest a do-while statement here?

        total = total + input;

    }while((input != 0); // Or How would i insert a second parameter that stops the loop when a number is entered twice in a row?

                  For the above parameters I know i would do && to start the second parameter, I just cannot figure out the logic statement I would insert as the parameter.

    System.out.println("The sum of the numbers is " + total);
}

}

Answer 1

您需要将最后一个输入保存在变量中，然后将其与实际输入进行比较（如果它们相等，则break while循环。

试试这个：

    int last_input = 0;
    int input = 0;
    int total = 0;
    int update = 0;

    Scanner inputDevice = new Scanner(System.in);

    do
    {   
        System.out.println("Enter any number");
        input = inputDevice.nextInt();

        total = total + input;

        if(last_input == input)
            break;

        last_input = input;

    }while(input != 0); // Or How would i insert a second parameter that stops the loop when a number is entered twice in a row?

    System.out.println("The sum of the numbers is " + total);

Answer 2

这很简单，您可以使用“普通”while循环执行此操作，例如用

替换do-while语句

while (true) {
    System.out.println("Enter any number");
    input = inputDevice.nextInt();            
    total = total + input;

    if ((input == 0) || (input == update)) {
        break; // Exit the loop
    } else {
        update = input; // Remember the last value
    }    
}

上面的示例重用了update变量，该变量似乎没有用于任何其他变量。如果需要它用于其他目的，它当然可以用另一个变量替换，在input的同一区域中声明。

Answer 3

int prevInput = 0;
bool bFirstRun = true

do
{
    System.out.println("Enter any number");

     if(!bFirstRun) 
      {
         prevInput = input
      }
    input = inputDevice.nextInt();

     bFirstRun = false;


    total = total + input;
     if(prevInput == input)
      break;

}while((input != 0);

我会在上面添加一个prevInput参数和一个布尔值来检查它是否是第一次通过循环。如果是，那么不检查先前的输入，如果它不是第一次通过那么检查输入到前一个（在它被添加到总数之后）并且如果它相同然后从循环中断。

Answer 4

在这里......试试这个。它更简单

int num1 = 0, num2 = 0, total = 0;

    do {
        num2 = num1;
        System.out.println("Enter any number");
        num1 = inputDevice.nextInt();
        total += num1;
        System.out.println("The sum of the numbers is " + total);
    } while (num1 != num2 && num1 != 0);

做声明问题

4 个答案: