using System;

// Demo: void function

​

// Actions vs Functions

// Actions for side-effects

// Functions for return

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void SayHello()

{

    Console.WriteLine("Hello, world");

}

​

SayHello();

Log("");

​

// Demo: function with parameters

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void SayHello(string name)

{

    Console.WriteLine("Hello, {0}", name);

}

​

SayHello("Doctor");

Log("");

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void SayHello2(string name = "world")

{

    Console.WriteLine("Hello, {0}", name);

}

​

SayHello2();

SayHello2("Doctor");

Log("");

​

// Demo: function with return value

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// PLEASE DON'T RETURN NULL!

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int AddTwoNumbers(int a, int b)

{

    Log("a: {0}", a);

    Log("b: {0}", b);

​

    var sum = a + b;

    return sum;

}

​

int x = 10, y = 5;

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Log("x: {0}", x);

Log("y: {0}", y);

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//Log("a: {0}", a);

//Log("b: {0}", b);

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var sum = AddTwoNumbers(5, 10);

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//Log("a: {0}", a);

//Log("b: {0}", b);

​

Log("sum: {0}", sum);

​

​

// Helper function

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void Log(string message, params object[] args)

{

    Console.WriteLine(message, args);

}