Access modifiers (public, private, internal) in C Sharp (C#) - Time & Space Complexity

Time Complexity: Access modifiers (public, private, internal)

O(1)

Understanding Time Complexity

When we use access modifiers like public, private, and internal, we control who can use parts of our code.

We want to understand how these choices affect the time it takes for the program to run.

Scenario Under Consideration

Analyze the time complexity of the following code snippet.

class Sample {
    private int secretNumber = 42;
    public int GetNumber() {
        return secretNumber;
    }
    internal void PrintNumber() {
        System.Console.WriteLine(secretNumber);
    }
}
    

This code defines a class with different access levels for its members.

Identify Repeating Operations

Identify the loops, recursion, array traversals that repeat.

• Primary operation: There are no loops or repeated operations here.
• How many times: Each method runs once when called.

How Execution Grows With Input

Since there are no loops or repeated steps, the time to run these methods stays the same no matter the input size.

Input Size (n)	Approx. Operations
10	Constant steps
100	Constant steps
1000	Constant steps

Pattern observation: The time does not grow with input size; it stays steady.

Final Time Complexity

Time Complexity: O(1)

This means the time to run these methods stays the same no matter how big the input is.

Common Mistake

[X] Wrong: "Making something private or internal makes the code slower because it adds checks."

[OK] Correct: Access modifiers only control who can use the code; they do not add extra steps that slow down the program.

Interview Connect

Understanding that access modifiers do not affect how fast code runs helps you focus on what really matters when writing efficient programs.

Self-Check

"What if the methods contained loops that depended on input size? How would the time complexity change?"