#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <numeric>

using namespace std;
int getMin(vector v)
{
    int minVal = INT_MAX;
    for (auto e : v)
        minVal = min(e, minVal);
    return minVal;
}
int calc(vector v1, vector v2)
{
    int sum1 = accumulate(v1.begin(), v1.end(), 0);
    int sum2 = accumulate(v2.begin(), v2.end(), 0);
    if (sum1 > sum2)
    {
        swap(v1, v2);
        swap(sum1, sum2);
    }
    int diff = sum2 - sum1;
    int ret = 0;
    if (diff == 0)
        return ret;
    else
    {
        while (diff > 0)
        {
            int tmp = 9 - getMin(v1);
            auto it = find(v1.begin(), v1.end(), getMin(v1));
            *it = 9;
            diff -= tmp;
            ++ret;
        }
    }
    return ret;
}
int main(int argc, char const *argv[])
{
    string str;
    cin >> str;
    vector v;
    for (auto s : str)
        v.emplace_back(s - '0');
    vector v1(v.begin(), v.begin() + 3);
    vector v2(v.begin() + 3, v.end());
    int res = calc(v1, v2);
    cout << res << endl;
    return 0;
}