Question

我正在尝试创建一个工具，将当前年份与事件发生年份进行比较，然后允许用户猜测自该事件发生以来已经过了多少年。例如，首届FRC锦标赛于1992年举行。当年是2015年。用户猜测它发生在23年前，这是正确的。

所以，在我看来，代码看起来像这样......

  public class Credits extends Activity {
    int inaugural = 1992;
    int guess;
    int differenceInYears;
    Calendar calendar = Calendar.getInstance();
    int year = calendar.get(Calendar.YEAR);
    int output;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_credits);
        final EditText yearGuess=(EditText)findViewById(R.id.txtYearGuess);
        Button go = (Button)findViewById(R.id.btnCalculate);
        final TextView result = ((TextView)findViewById(R.id.txtResult));
        go.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                int userGuess= Integer.parseInt(yearGuess.getText().toString());
                differenceInYears = year - inaugural;
                output = userGuess - differenceInYears;

                if (output < 1) {
                    result.setText("Guess again! You guessed too low!");
                }

                else if (output == 1) {
                    result.setText("You're REALLY close!");

                }

                else if (output == -1) {
                    result.setText("You're REALLY close!");

                }

                else if (output > 1) {
                    result.setText("Guess again! You guessed too high!");

                }

                else {
                    result.setText("Good job! You're an FRC Genious!");

                }
            }

        });
     }
    }

...但是，测试时值继续出错。我在这里错过了什么？我的数学有问题吗？还是代码？或两者兼而有之？

Answer 1

它与你的if语句的逻辑有关。当用户猜对时，＆＃34;输出＆＃34;应该等于0，这会被你的第一个条件抓住。

Answer 2

简单的逻辑错误。

if (output < 1) {
                    result.setText("Guess again! You guessed too low!");
                }

应该是......

if (output < -1) {
                    result.setText("Guess again! You guessed too low!");
                }

忘记让低比较为负。

年度比较工具的逻辑错误

2 个答案: