import java.io.*;
import java.util.StringTokenizer;

public class AverageWithArray
{

	static BufferedReader keyboard = new BufferedReader 
										    	(new InputStreamReader (System.in));

	public static double ComputeAverage(int[] list)
	{
		int sum = 0;
		int i;
		for (i = 0; i < list.length; i ++)
		{
			if (list[i] < 0)
				break;
			else
				sum = sum + list[i];
		}
			
		return (double) sum/(i);
	}
	
	public static void runProgram() throws IOException
	{
		int i;
		
		StringTokenizer tokenizer = new StringTokenizer(keyboard.readLine());
		
		int numTokens = tokenizer.countTokens();
		
		int[] list = new int[numTokens];
		
		for (i = 0; i < numTokens; i ++)
			list[i] = Integer.parseInt(tokenizer.nextToken());
		
		double average = ComputeAverage(list);
		
		System.out.println("The average of the integers entered " +
								"was " +  average + ".");
	}

	public static void main(String args[]) throws IOException
	{
		System.out.println("Please enter numbers separated by spaces, ending with a "
								+ "carriage return");
	
		runProgram();
	}
}