#include<iostream>
#include<algorithm>
using namespace std;

int main(){

  double a[10000],n,a_max=0,a_min=1.79769e+308;
  int i=0;

  while(cin >> n){

    a_max = max(a_max,n);
    a_min = min(a_min,n);

  }

  a_max -= a_min;

  cout << a_max << endl;

}