Recursion Examples

RecursionExamples.cs

void Main()
{
	var x = 19;
	var y = 7;
	Console.WriteLine($"Factorial of x={x}, result={Factorial(x)}.\n");
	Console.WriteLine($"Multiplication of x*y={x}*{y}={Multiplication(x, y)}.\n");
	Console.WriteLine($"Binary of x={x}, result={DecimalToBinary(x)}.\n");
}

public long Factorial(long x)
{
	if(x == 0 || x == 1) return 1;
	return x * Factorial(x-1);
}

public long Multiplication(long x, long y)
{
	if(x == 0 || y == 0) return 0;
	return x + Multiplication(x, y-1);
}

public string DecimalToBinary(long x)
{
	if(x == 0 || x == 1) return x.ToString();
	return DecimalToBinary(x / 2) + (x % 2).ToString();
}

//Note: Another way to program
//public long Factorial(long x) => (x == 0 || x == 1) ? 1 : x * Factorial(x-1);
//public long Multiplication(long x, long y) => (x == 0 || y == 0) ? 0 : Multiplication(x, y-1);
//public string DecimalToBinary(long x) => x == 0 || x == 1 ? x.ToString() : DecimalToBinary(x / 2) + (x % 2).ToString();