java - 如何让这个变量稍后在方法中被识别？

Question

大家好，我正在编写一个数学测验程序作为学习练习，我无法在方法的后面识别这个“响应”变量。特别是带有 *s 的'response' 变量不会链接到之前声明的响应变量。我是编程新手，所以很确定我犯了一个基本错误，但我无法解决，如果有人能帮助我，我将不胜感激。谢谢!

import acm.util.*;
import acm.program.*;


public class MathsQuiz extends ConsoleProgram{

    public void run(){
        println("This program gives atudents a series of maths questions");
        askQuestions();
    }

    private void askQuestions(){
        for (int i = 0; i < NUMBER_OF_QS; i++){
            askQ();
        }
    }

    private void askQ(){
        int answer = rgen.nextInt(0,20);
        int number1 = rgen.nextInt(0,20);
        int number2 = answer - number1;

        if (number2 > 0){
            int response = readInt("What is " + number1 + "+" + number2 + "?");

        }else {
            int response = readInt("What is " + number1 + " " + number2 + "?");
        }

                if (**response** == answer){
                    println("Correct!");
                }else{
                    println("Incorrect");
                }
        }


    private RandomGenerator rgen = RandomGenerator.getInstance(); 

    int NUMBER_OF_QS = 5;
    int RES = 0;
}

Answer 1

将 response 移动到外部范围:

int response;

if (number2 > 0) {
    response = readInt("What is " + number1 + "+" + number2 + "?");
} else {
    response = readInt("What is " + number1 + " " + number2 + "?");
}

Local variables have the most limited scope. Such a variable is accessible only from the function or block in which it is declared. The local variable's scope is from the line they are declared on until the closing curly brace of the method or code block within which they are declared.