Question

import java.util.Scanner;
import java.util.Random;

public class ResponseTimeProject
{
  public static void main(String[] args) {

    Scanner in = new Scanner(System.in);
    Random rand = new Random();

    System.out.print("Please enter your full name: ");
    String name = in.nextLine();

    System.out.println("Hello " + name + ". Please answer as fast as you can." + "\n\nHit <ENTER> when ready for the question.");
    in.nextLine();

    for (int count = 0; count < 4; count ++) {

      String alphabet="ABCDEFGHIJKLMNOPQRSTUVWXYZ";

      int character=(int)(Math.random()*26);

      String s = alphabet.substring(character, character+1);

      Random r = new Random();
      int i;

      for (i = 0; i < 1; i++) {
        System.out.println(alphabet.charAt(r.nextInt(alphabet.length())));
      }

      long startTime = System.currentTimeMillis();

      System.out.print("What is the next letter in the alphabet?" + " ");
      String response = in.nextLine();

      long endTime = System.currentTimeMillis();

      String outcome;

      if (alphabet.substring(character+1, character+2).equals(response)) {
        outcome = "Correct!";
      } else {
        outcome = "Incorrect.";
      }

      long reactionTime = endTime - startTime;
      System.out.println(outcome);
      System.out.println("The average time it took you was " + reactionTime + " milliseconds"); 
      System.out.println("Thank you "  + name + ", goodbye.");

    }
  }
}

HELP：此代码运行但它给了我错误的答案。我不知道出了什么问题。它打印不正确的结果。不知道我需要修复什么

Answer 1

有问题的代码实际上是一团糟（从字符串中获取字符的子字符串，单个迭代的循环等）。但与此问题相关的基本问题是字母表中的下一个字母＆＃34;取决于打印但从未存储的输出。目前正在

for (i = 0; i < 1; i++) {
    System.out.println(alphabet.charAt(r.nextInt(alphabet.length())));
}

因此从未保存过，所以没有什么比较它。

所以，保存下一个字符，然后打印出来。

char nextLetter = alphabet.charAt(r.nextInt(alphabet.length());

然后在比较中，对于响应，检查对实际值的响应，而不是字母表String中的一些随机子串。

response = in.nextLine();
char chkChar = response.charAt(0);
if (chkChar == nextLetter) {
  ...
}

打印不正确，但仍在运行

1 个答案: