Untitled

string[] grades = { "A", "B", "C", "D", "E", "F", "F", "F" };
int countA = 0, countB = 0, countC = 0, countD = 0, countE = 0, countF = 0;

foreach (string grade in grades)
{
    switch (grade)
    {
        case "A":
            countA++;
            break;
        case "B":
            countB++;
            break;
        case "C":
            countC++;
            break;
        case "D":
            countD++;
            break;
        case "E":
            countE++;
            break;
        case "F":
            countF++;
            break;
        default:
            Console.WriteLine($"Okänt betyg: {grade}");
            break;
    }
}

Console.WriteLine($"A: {countA}");
Console.WriteLine($"B: {countB}");
Console.WriteLine($"C: {countC}");
Console.WriteLine($"D: {countD}");
Console.WriteLine($"E: {countE}");
Console.WriteLine($"F: {countF}");