Menu
CoddyTech

评分逻辑

本课属于 Coddy C# 学习旅程的“逻辑与流程”单元。第 43 课,共 66 课。

challenge icon

挑战

简单

现在我们已经可以分析数据,接下来实现一个评分系统,根据分数分配字母等级。创建一个名为 GradingSystem 的类,并添加以下方法:

  1. ConvertToLetterGrade(double score):根据以下等级标准,将数值分数转换为字母等级:
    • A:90-100
    • B:80-89
    • C:70-79
    • D:60-69
    • F:0-59
    • 无效分数:如果分数无效(小于 0 或 > 100),则返回 "N/A"
  2. GetStudentGrade(int[][] scoreGrid, int studentIndex):计算某个学生的平均分,并返回其字母等级。学生索引无效时,返回 "N/A"。
  3. GetClassDistribution(int[][] scoreGrid):返回一个整数数组,表示班级中每个字母等级的人数 [A, B, C, D, F]。根据每个学生的平均分统计。

亲手试试

using System; // 不要删除这一行
public class GradingSystem
{
    public static string ConvertToLetterGrade(double score)
    {
        // 在这里编写你的代码
        
    }
    
    public static string GetStudentGrade(int[][] scoreGrid, int studentIndex)
    {
        // 在这里编写你的代码
        
    }
    
    public static int[] GetClassDistribution(int[][] scoreGrid)
    {
        // 在这里编写你的代码
        
    }
}

// 测试所需,请勿修改
public class DataCollector
{
    public static int[][] CreateScoreGrid(int students, int assignments)
    {
        int[][] scoreGrid = new int[students][];
        for (int i = 0; i < students; i++)
        {
            scoreGrid[i] = new int[assignments];
        }
        return scoreGrid;
    }
    
    public static bool ValidateScore(int score)
    {
        return score >= 0 && score <= 100;
    }
    
    public static int[][] PopulateWithDefaultValues(int[][] scoreGrid)
    {
        for (int i = 0; i < scoreGrid.Length; i++)
        {
            for (int j = 0; j < scoreGrid[i].Length; j++)
            {
                scoreGrid[i][j] = -1;
            }
        }
        return scoreGrid;
    }
}

public class DataEntry
{
    public static int SetStudentScore(int[][] scoreGrid, int studentIndex, int assignmentIndex, int score)
    {
        // 检查索引是否越界
        if (studentIndex < 0 || studentIndex >= scoreGrid.Length || 
            assignmentIndex < 0 || assignmentIndex >= scoreGrid[studentIndex].Length)
        {
            return -1;
        }
        
        // 验证分数
        if (!DataCollector.ValidateScore(score))
        {
            return -2;
        }
        
        // 设置分数
        scoreGrid[studentIndex][assignmentIndex] = score;
        return 0;
    }
    
    public static int UpdateAllScores(int[][] scoreGrid, int[] studentIndices, int assignmentIndex, int score)
    {
        int successCount = 0;
        
        for (int i = 0; i < studentIndices.Length; i++)
        {
            int result = SetStudentScore(scoreGrid, studentIndices[i], assignmentIndex, score);
            if (result == 0)
            {
                successCount++;
            }
        }
        
        return successCount;
    }
}

public class DataAnalyzer
{
    public static double CalculateStudentAverage(int[][] scoreGrid, int studentIndex)
    {
        // 检查学生索引是否有效
        if (studentIndex < 0 || studentIndex >= scoreGrid.Length)
        {
            return -1;
        }
        
        int sum = 0;
        int count = 0;
        
        // 计算有效分数的总和
        for (int j = 0; j < scoreGrid[studentIndex].Length; j++)
        {
            int score = scoreGrid[studentIndex][j];
            if (score != -1)  // 忽略未评分的作业
            {
                sum += score;
                count++;
            }
        }
        
        // 返回平均分;如果没有有效分数,则返回 0
        return count > 0 ? (double)sum / count : 0;
    }
    
    public static double CalculateAssignmentAverage(int[][] scoreGrid, int assignmentIndex)
    {
        // 检查是否有学生
        if (scoreGrid.Length == 0)
        {
            return -1;
        }
        
        // 检查作业索引是否有效
        if (assignmentIndex < 0 || assignmentIndex >= scoreGrid[0].Length)
        {
            return -1;
        }
        
        int sum = 0;
        int count = 0;
        
        // 计算该作业有效成绩的总和
        for (int i = 0; i < scoreGrid.Length; i++)
        {
            if (assignmentIndex < scoreGrid[i].Length)
            {
                int score = scoreGrid[i][assignmentIndex];
                if (score != -1)  // 忽略未评分的作业
                {
                    sum += score;
                    count++;
                }
            }
        }
        
        // 返回平均分;如果没有有效分数,则返回 0
        return count > 0 ? (double)sum / count : 0;
    }
    
    public static int[] FindHighestScore(int[][] scoreGrid)
    {
        int highestStudentIndex = 0;
        int highestAssignmentIndex = 0;
        int highestScore = -1;
        
        // 查找最高成绩
        for (int i = 0; i < scoreGrid.Length; i++)
        {
            for (int j = 0; j < scoreGrid[i].Length; j++)
            {
                int currentScore = scoreGrid[i][j];
                if (currentScore > highestScore)
                {
                    highestScore = currentScore;
                    highestStudentIndex = i;
                    highestAssignmentIndex = j;
                }
            }
        }
        
        return new int[] { highestStudentIndex, highestAssignmentIndex, highestScore };
    }
}

逻辑与流程中的所有课

自己练习: C# 在线编译器