/*****************************************************************************************************
*
*	myRandomWalkers.java
*
*****************************************************************************************************/

public class myRandomWalkers {

	public static void main(String[] args) {
		int N = Integer.parseInt(args[0]);
		int T = Integer.parseInt(args[1]); //number of trials to be simulated in program
		int x = 0;  //starting position for x coordinate
		int y = 0;  //starting position for y coordinate
		double r;
		int step; //for loop should repeat until 'N' 'steps' are walked
		int trial; //program should repeat until 'T' number of 'trials" are run
		long average = 0;
		double square;
		double root;

		for (trial = 0; trial<T; trial++) {
			for(step = 0; step<N; step++){
				r = Math.random();
				if (r<.25)
					{x++;}
				else if (r<.5)
					{y++;}
				else if (r<.75)
					{x--;}
				else	{y--;}
			} 
			square = ((x*x)+(y*y));
			root = Math.sqrt(square);
			average += root;	
		}
		System.out.println("mean squared distance: " + (average / T));
	}
}