Output Parameter In C Sharp

This program descirbe the concept of Output Parameter in C#
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using System;

class OutputParameter
{
static void Main()
{
int a = 10,b =20;
int c; //Notice i did not assign any value variable b.
Sum(a,b,out c);

Console.WriteLine("The value after sum is " + c);
}
static void Sum(int a, int b, out int c)
{
c = a+ b;
}
}

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