#include <iostream>
#include <algorithm>
#include <stdio.h>
#include <string.h>
#include <string>
#include <math.h>
#include <cmath>
#include <cstring>
#include <sstream>
#include <stdlib.h>
#include <iomanip>
//#include <vector>

using namespace std;

int main (void)
{
	long double a = 0.0,b = 1000000.0,p;
	int co = 0;
	while (cin >> p)
	{
		if (a < p)
		{
			a = 0.0;
			a = p;
		}
		if (b > p)
		{
			b = 0.0;
			b = p;
		}
		p = 0;
	}

	cout << a - b << endl;
	return 0;
}




