Enum declaration syntax in C Sharp (C#) - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this enum usage?

Consider this C# code snippet. What will be printed when it runs?

C Sharp (C#)

enum Days { Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday }

class Program {
    static void Main() {
        Days today = Days.Wednesday;
        Console.WriteLine((int)today);
    }
}

A 0

B 2

C 3

D 4

💡 Hint

Remember enums start numbering from 0 by default.

By default, the first enum member has the value 0, so Sunday=0, Monday=1, Tuesday=2, Wednesday=3. Casting Wednesday to int prints 3.

❓ Predict Output

intermediate

What is the output of this enum with custom values?

Look at this enum with assigned values. What does the program print?

C Sharp (C#)

enum Status { Pending = 1, Active = 5, Closed = 10 }

class Program {
    static void Main() {
        Status s = Status.Active;
        Console.WriteLine((int)s);
    }
}

A 5

B 10

C 1

D 0

💡 Hint

Check the assigned value for Active.

Active is explicitly assigned the value 5, so casting it to int prints 5.

❓ Predict Output

advanced

What error does this enum declaration cause?

What error will this code produce when compiled?

C Sharp (C#)

enum Colors { Red, Green = 5, Blue, Green = 10 }

class Program {
    static void Main() {}
}

A Compile-time error: Enum values must be unique

B Runtime error: Duplicate enum member

C No error, compiles successfully

D Compile-time error: Duplicate enum member name

💡 Hint

Check if enum member names can repeat.

Enum member names must be unique. Declaring 'Green' twice causes a compile-time error.

❓ Predict Output

advanced

What is the output of this enum with flags attribute?

Given this code using [Flags], what will be printed?

C Sharp (C#)

[Flags]
enum Permissions {
    None = 0,
    Read = 1,
    Write = 2,
    Execute = 4
}

class Program {
    static void Main() {
        Permissions p = Permissions.Read | Permissions.Write;
        Console.WriteLine(p);
    }
}

A Read, Write

B 3

C Read Write

D 1, 2

💡 Hint

The [Flags] attribute changes how the enum prints combined values.

With [Flags], combined enum values print as a comma-separated list of names.

🧠 Conceptual

expert

Which enum declaration is valid and assigns correct values?

Which of these enum declarations compiles without error and assigns the values as shown?

A enum Levels { Low = 1, Medium = 2, High = 5, Critical = 5 } // Duplicate value 5

B enum Levels { Low = 1, Medium, High = 5, Critical } // Low=1, Medium=2, High=5, Critical=6

C enum Levels { Low, Medium = 2, High, Critical } // Low=0, Medium=2, High=3, Critical=4

D enum Levels { Low = 1, Medium = 2, High, Critical = 2 } // Duplicate value 2

💡 Hint

Check how enum values increment when not explicitly assigned.

Option B is valid: Medium gets 2 automatically after Low=1; Critical gets 6 after High=5. Duplicate values are allowed but not in options B and D as stated.