#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>
#include <complex>
#include <cassert>

using namespace std;
using ll = long long;

int main(){

    vector<char> c(3);
    for (int i=0; i<3; i++) cin >> c[i];
    sort(c.begin(), c.end());
    cout << c[2]-c[0] << endl;

    return 0;
}