Problem: There is data that records the altitude of mountains that have been climbed so far. Create a program that reads this data and outputs the elevation difference between the highest and lowest mountains.



Input

The input is given in the following format:


Mountain height
...
...


The height of the mountain is given over multiple lines. All values ​​entered are real numbers greater than or equal to 0 and less than or equal to 1,000,000. The number of mountain heights entered is 50 or less.

Output

The elevation difference between the highest mountain and the lowest mountain is output as a real number. The output may contain an error of 0.01 or less.

Example

Input

3776.0
1819.0
645.2
2004.1
1208.6


Output

3130.8

Solution (in JAVA):

Solution:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
	private	static	BufferedReader	br = null;

	static {
		br = new BufferedReader(new InputStreamReader(System.in));
	}

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		String	strIn = null;
		double	in    = 0.0;
		double	max   = Double.MIN_VALUE;
		double	min   = Double.MAX_VALUE;
		boolean	bflag = false;

		while ((strIn = parseStdin()) != null) {
			in    = Double.parseDouble(strIn);
			max   = Math.max(max, in);
			min   = Math.min(min, in);
			bflag = true;
		}

		if (bflag) {
			System.out.println(max - min);
		}
	}

	private static String parseStdin() {
		String	strNum = null;

		try {
			String line = br.readLine();
			if (line != null) {
				if (!line.isEmpty()) {
					strNum = line;
				}
			}
		}
		catch (IOException e) {}

		return strNum;
	}
}