Operators and Math

View, run, and experiment with Operators and Math in CodeUtility's online C# IDE.

Version

Pre-installed Libs

🚀 351,494 total executions (748 this month)

Output

Practice C# with coding challenges

Solve hands-on problems right in this editor: run the sample tests, submit, and get an AI code review.

All C# challenges

Easy

Average of Three

Average three whole numbers.

You'll learn ArithmeticDivision

BeginnerLearning-pathVariables

View solutions (1)

Easy

Rectangle Perimeter

Compute the perimeter of a rectangle from its sides.

You'll learn ArithmeticReturn values

BeginnerLearning-pathVariables

View solutions (1)

Easy

Join Customers and Orders

Join customers with their orders like a LINQ Join and report each customer's total spend.

You'll learn LINQ JoinGrouping

ArraysSorting

No solutions yet

Easy

To-Do List

Keep a list of tasks: add them, mark them done, remove them and report what is still pending.

You'll learn Typed collectionsRecords

BeginnerSimulationStrings

No solutions yet

Easy

Linked List Operations

Simulate a linked list: add at either end, remove from the front or by value, and reverse it.

You'll learn Linked listsSimulation

Data-structuresSimulation

No solutions yet

Easy

Sum a Flat JSON Object

Parse a flat JSON object whose values are integers and add up the values.

You'll learn JSON parsingString splitting

ParsingStrings

No solutions yet

Easy

WhenAll Total Time

Find how long a program takes when each group of tasks runs together with Task.WhenAll and groups run one after another.

You'll learn Async/awaitTask.WhenAll

ArraysBeginner

No solutions yet

Medium

Parallel Task Completion Order

Run tasks concurrently with at most k at a time and report the order in which they finish.

You'll learn ConcurrencyPriority queues

SimulationSorting

No solutions yet

Medium

Min Stack

Build a stack that reports its smallest element instantly after any push or pop.

You'll learn StacksRunning minimum

Data-structuresStacks

No solutions yet

Easy

Unique Records

Remove duplicate records that are equal by value, keeping the first of each in order.

You'll learn RecordsValue equality

BeginnerStrings

No solutions yet

Easy

Sort by a Chosen Key

Sort people by name or by age with a comparer chosen at run time, breaking ties consistently.

You'll learn ComparersSorting

ArraysSorting

No solutions yet

Medium

Weekly Payroll

Total a week's pay for salaried, hourly and commission employees, each paid by its own rule.

You'll learn PolymorphismOvertime math

ParsingSimulationmath

No solutions yet

Learn and practise C#

Follow a learning path with runnable lessons, then test yourself with coding challenges.

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This tool uses dotnet-script under the hood to compile and execute your code with true .NET behavior, allowing you to experiment with both basic and advanced C# features like LINQ, async/await, pattern matching, and generics.

You can test simple scripts, functions, and logic flows, or explore concepts like classes, structs, inheritance, and interfaces - all in a clean, distraction-free coding environment.

Whether you’re learning C#, testing algorithms, or experimenting with .NET features, the CodeUtility C# Executor gives you a fast, secure, and reliable way to run C# code instantly from any browser.

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Use a multi-file editor, an isolated execution terminal, runtime-specific libraries, persistent workspaces, sharing, and real-time collaboration from the same executor.

How to use this executor?

Choose a runtime, open or create a file, write your code, and select Run. Output appears in the terminal, while signed-in users can keep files in a workspace, install libraries, and collaborate through shares.

Select a version and edit the current file or open another workspace file.
Run the code, provide input in the terminal when requested, and review saved run history.
Use libraries, workspace tools, sharing, and chat when your task needs more than one snippet.

Start coding

VersionSelect a runtime before running. Installed libraries belong to the selected language version.
Open files lists unopened text files. Select one to open it in an available editor tab.
Run executes the active file with its workspace available to the program.
Stop ends the current execution before its time limit.
Advanced Mode opens the IDE layout with a file explorer and movable, resizable terminal.

Workspace and libraries

New file creates a file in the selected parent directory and opens it in the editor.
New folder creates a directory, up to the supported nesting depth.
Upload files adds one or more safe files to a directory.
Download saves a file or a zipped directory to your device.
Copy duplicates a workspace file or directory.
Rename changes a file name and updates its open tab and history.
Move relocates an item; files and directories can also be dragged.
Delete removes an item after confirmation and closes its open editor tab.
Pre-installed Libs shows packages already included in this runtime.
Add Lib installs a private package for your account and selected runtime.

Terminal and assistance

Run history opens previous and next saved outputs.
Copy output copies the current terminal text.
Clear output removes all saved run outputs after confirmation.
Explain summarizes the active code.
Recents opens recent explanations and results.
Settings changes fonts, themes, and visible toolbar buttons.

Sharing and collaboration

Share publishes the current file, a directory, or the whole workspace as a snapshot or live workspace. You control link access and who may save changes.
Logs records saved collaborator actions in a shared workspace.
Share chat lets signed-in participants message, mention people, share code blocks, and see online or typing members.
Live collaboration shows collaborator cursors and saved file updates. View-only users can load the latest version or keep temporary edits.

Quotas and limits

Execution time is limited to 20 seconds per server run. Use Stop when you want to end it sooner.
Workspace storage allows 100 files, 100 directories, and 10 MiB total for each signed-in user workspace and language.
Files and folders are limited to 1 MiB per file and 5 nested directory levels. Files generated by your code follow the same quota.
Private libraries are limited to 10 installed packages for each account and runtime.
Share snapshots can contain up to 100 files, 1 MiB per file, and 2 MiB total.
Share invitations support up to 25 people per share, with access and saving permissions managed separately.
Share chat allows 2,000 characters per message and 10,000 messages per share.
Quota enforcement also applies while code is running. A write that exceeds file count, size, storage, or nesting limits is rejected safely.

Good to know Only run code and install packages you trust. Execution is isolated and limited, but your program can still modify files inside a writable workspace up to its enforced quota.

💡 C# Basics & Examples You Can Try Above

1. Declaring Variables and Constants

C# uses strongly-typed variable declarations. Use const for compile-time constants and readonly for runtime constants.

int age = 30;
double pi = 3.14159;
char grade = 'A';
string name = "Alice";
bool isActive = true;

// Constants
const int MaxUsers = 100;
const string Company = "CodeUtility";

2. Conditionals (if / switch)

Use if, else if, and switch for control flow.

int x = 2;
if (x == 1)
{
    Console.WriteLine("One");
}
else if (x == 2)
{
    Console.WriteLine("Two");
}
else
{
    Console.WriteLine("Other");
}

switch (x)
{
    case 1:
        Console.WriteLine("One");
        break;
    case 2:
        Console.WriteLine("Two");
        break;
    default:
        Console.WriteLine("Other");
        break;
}

3. Loops

C# supports for, while, and foreach loops.

for (int i = 0; i < 3; i++)
{
    Console.WriteLine(i);
}

int n = 3;
while (n > 0)
{
    Console.WriteLine(n);
    n--;
}

4. Arrays

Arrays store fixed-size collections of elements of the same type.

int[] numbers = { 10, 20, 30 };
Console.WriteLine(numbers[1]);

5. List Manipulation

Use List<T> for dynamic collections.

List<int> nums = new List<int> { 1, 2, 3 };
nums.Add(4);
nums.Remove(2);

foreach (int n in nums)
{
    Console.Write(n + " ");
}

6. Console Input/Output

Use Console.WriteLine and Console.ReadLine for basic I/O.

Console.Write("Enter your name: ");
string name = Console.ReadLine();
Console.WriteLine($"Hello, {name}!");

7. Functions

Define methods using a return type, name, and parameters.

int Add(int a, int b)
{
    return a + b;
}

Console.WriteLine(Add(3, 4));

8. Dictionaries

Dictionary<TKey, TValue> stores key-value pairs.

Dictionary<string, int> ages = new Dictionary<string, int>();
ages["Alice"] = 30;
Console.WriteLine(ages["Alice"]);

9. Exception Handling

Handle runtime errors using try, catch, and finally.

try
{
    throw new Exception("Something went wrong");
}
catch (Exception ex)
{
    Console.WriteLine(ex.Message);
}

10. File I/O

Use File and StreamReader/StreamWriter for file operations.

File.WriteAllText("file.txt", "Hello File");
string text = File.ReadAllText("file.txt");
Console.WriteLine(text);

11. String Manipulation

C# strings support methods like Length, Substring, Contains.

string message = "Hello World";
Console.WriteLine(message.Length);
Console.WriteLine(message.Substring(0, 5));
Console.WriteLine(message.Contains("World"));

12. Classes & Objects

C# supports object-oriented programming through classes and objects.

class Person
{
    public string Name;
    public Person(string name) => Name = name;
    public void Greet() => Console.WriteLine($"Hi, I'm {Name}");
}

Person p = new Person("Alice");
p.Greet();