#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int main()
{
    double a[1000];
    int i=0;
    while(cin>>a[i])i++;
    sort(a,a+i);
    reverse(a,a+i);
    cout<<a[0]-a[i-1]<<endl;
    //for(int j=0;j<100;j++)
    //{
    //    cout<<"a["<<j<<"]="<<a[j]<<endl;
    //}
    return 0;
}