using System;
using System.IO;

class CreateInputFileForFFT
{
	static void Main(string[] args)
	{
		string fileName = "input.txt";

		FileStream f = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.Write);
		StreamWriter wr = new StreamWriter(f);

		uint n = (uint) System.Convert.ToInt32(args[0]);
		wr.WriteLine("{0}", n);

		Random r = new Random();
		double v1, v2;

		for (int i = 0; i < n; i++)
		{
			v1 = r.NextDouble() * 10;
			v2 = r.NextDouble() * 10;
			wr.WriteLine("{0} {1}", v1, v2);
		}
	    
		wr.Close();
	}
}