#include <bits/stdc++.h>
#define int long long
#define ll long long
#define rep(i,n) for(int i=0;i<n;i++)
#define INF LLONG_MAX/3
#define eps LDBL_EPSILON
#define moder (1000000007)
#define pie acos(-1)
#define P std::pair<int,int>
#define prique priority_queue
#define ggr getchar();getchar();return 0;
using namespace std;
signed main(){
	double a[50]={};
	int i=0;
	for(;cin>>a[i];i++);
	sort(a,a+i);
	cout<<a[i-1]-a[0]<<endl;
}
