在比较C＃中的两个数组后如何修复输出？

Question

所以我有这个功课分配，要求我在比较两个数组后将输出分配给标签。我的问题是，在比较两个数组后，我分配的输出是错误的。如果在两个数组的特定索引相等时我应该输出'Y'，如果它们不相等则为'N'但是每次运行代码时，它都会向所有标签输出'Y'，无论是什么。如何在比较后修复输出内容？

     private void evaluateStudentAnswers()
        {
            /* Use a "for" loop to cycle through the answerKey[] and studentAnswers[] arrays, and compare the answers
             * in the two arrays at each index.  If they match, then increment the global variable "correctAnswers"
             * and assign the value 'Y' to the corresponding index in the correctOrIncorrect[] array.  if they
             * don't match, then increment the global variable "incorrectAnswers" and assign the value 'N' to the
             * corresponding indes in the correctOrIncorrec[] array.  These two variables will be used to calculate
             * the grade percentage.
             */

            for (int i = 0; i < studentAnswers.Length; i++)
            {
                for(int j = 0; j < answerKey.Length; j++)
                {
                    // I think the indexes below are being checked if they're the same and I need to make sure not just the
                    //indexes are the same but the values as well 
                    if (studentAnswers[i] == answerKey[j]) 
                    {
                        correctAnswers++;

                        for(int k = 0; k < correctOrIncorrect.Length; k++)
                        {
                            correctOrIncorrect[k] = 'Y';
                        }
                    }

                    else
                    {
                        incorrectAnswers++;

                        for (int k = 0; k < correctOrIncorrect.Length; k++)
                        {
                            correctOrIncorrect[k] = 'N';
                        }
                    }
                }
            }
        }

Answer 1

我认为你的代码可以简化很多。假设studentAnswers和answerKey之间有1-1的映射。

for (int i = 0; i < studentAnswers.Length; i++)
{
    var studentAnswer = studentAnswers[i];
    var answer = answerKey[i];
    if (studentAnswer == answer)
    {
        ++correctAnswers;
        correctOrIncorrect[i] = 'Y';
    }
    else
    {
        ++incorrectAnswers;
        correctOrIncorrect[i] = 'N'
    }
}

所有阵列都是相同的大小。因此，当我们循环学生提供的每个答案时，我们知道我们可以在answerKey中找到相应的正确答案。此外，正确答案的跟踪也遵循相同的模式，对于每个studentAnswer，我们想要在correctOrIncorrect中记录正确性，这对应于学生提供的特定答案。因此，我们只需要执行单个循环，因为i在我们正在处理时引用所有数组中的适当索引。

Answer 2

如果studentAnswers.Length == answerKey.Length == correctOrIncorrect.Length

然后

for (int i = 0; i < studentAnswers.Length; i++)
{
  if(studentAnswers[i] == answerKey[j])
  {
    correctAnswers++;
    correctOrIncorrect[k] = 'Y';
  }
  else
  {
    incorrectAnswers++;
    correctOrIncorrect[k] = 'N';
  }
}

Answer 3

由于这是一项任务我不会给出答案:)但是因为你被困，我鼓励你使用下面的指导。

您的代码中不需要这两个

1. 内部for-loop on correctOrIncorrect []
2. 变量“k”，您可以使用“i”代替correctOrIncorrect值赋值

Answer 4

由于数组必须具有相同的大小/顺序，因此您只需要遍历它们一次。另外，我发现三元分配比块更明确：

Func<bool, int> toInt = (b) => b ? 1 : 0;
for (int i = 0; i < studentAnswers.Length; i++)
{
    var studentAnswer = studentAnswers[i];
    var answer = answerKey[i];
    var isCorrect = studentAnswer == answer;
    correctOrIncorrect[i] = isCorrect ? 'Y' : 'N';
    correctAnswers = isCorrect ? 1 : 0; // toInt(isCorrect)
    incorrectAnswers = !isCorrect ? 1 : 0; // toInt(!isCorrect)
   }
}

Answer 5

或者在LINQ中（仅仅因为它值得学习，但可能不适合做作业）：

correctOrIncorrect = answerKey.Zip(studentAnswer, (a,b) => a == b ? "Y" : "N").ToArray();
incorrectAnswers = correctOrIncorrect.Count(x => x == "Y");
...