循环用户输入，直到满足条件

Question

我需要让用户输入一个数字以用作范围的开始，然后输入另一个数字作为范围的结束。起始编号必须为0或更大，结束编号不能大于1000。两个数字都必须被10整除。我找到了满足这些条件的方法，但是如果不满足这些条件，我的程序只会告诉用户他们的输入不正确。我是否可以对它进行编码，以便在用户输入后进行检查以确保满足条件，如果条件没有环回，请再次输入。这是我到目前为止的代码。

    Scanner keyboard = new Scanner(System.in);
    int startr;
    int endr;
    System.out.println("Enter the Starting Number of the Range: ");
    startr=keyboard.nextInt();
    if(startr%10==0&&startr>=0){
        System.out.println("Enter the Ending Number of the Range: ");
        endr=keyboard.nextInt();
        if(endr%10==0&&endr<=1000){

        }else{
            System.out.println("Numbers is not divisible by 10");
        }
    }else{
        System.out.println("Numbers is not divisible by 10");
    }

Answer 1

轻松做：

Scanner keyboard = new Scanner(System.in);
int startr, endr;
boolean good = false;
do
{
  System.out.println("Enter the Starting Number of the Range: ");
  startr = keyboard.nextInt();
  if(startr % 10 == 0 && startr >= 0)
    good = true;
  else
    System.out.println("Numbers is not divisible by 10");
}
while (!good);

good = false;
do
{
    System.out.println("Enter the Ending Number of the Range: ");
    endr = keyboard.nextInt();
    if(endr % 10 == 0 && endr <= 1000)
      good = true;
    else
      System.out.println("Numbers is not divisible by 10");
}
while (!good);

// do stuff