public static void Main()
Console.Write("Please enter your score in range 0-100\n");
score = int.Parse(Console.ReadLine());
Console.Write("Your grade is : F\n");
else if (score >= 50 && score < 60)
Console.Write("Your grade is : D\n");
else if (score >= 60 && score < 70)
Console.Write("Your grade is : C\n");
else if (score >= 70 && score < 80)
Console.Write("Your grade is : B\n");
Console.Write("Your grade is : A\n");
Console.Write("End program\n");