// 21:30
#define DEBUG 0
#include <algorithm>
#include <cmath>
#include <cstring>
#include <deque>
#include <iostream>
#include <map>
#include <set>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using pll = pair<ll, ll>;
using tll = tuple<ll, ll, ll>;
#define pb push_back
#define all(v) v.begin(), v.end()
#define for1(i, n) for (ll i = 0; i < (n); i++)
#define for2(i, m, n) for (ll i = (m); i < (n); i++)
#define for3(i, m, n, d) for (ll i = (m); i < (n); i += (d))
#define INF (1LL << 60)
#if DEBUG
#define dump(v1) dump_1(#v1, v1)
#define dump2(v1, v2) dump_2(#v1, v1, #v2, v2)
#define dump3(v1, v2, v3) dump_3(#v1, v1, #v2, v2, #v3, v3)
#else
#define dump(v1)
#define dump2(v1, v2)
#define dump3(v1, v2, v3)
#endif
#if DEBUG
template <typename T> void dump_1(const string &n1, const T &v1) {
    cerr << n1 << ": " << v1 << endl;
}
template <typename T1, typename T2>
void dump_2(const string &n1, const T1 &v1, const string &n2, const T2 &v2) {
    cerr << n1 << ": " << v1 << "  " << n2 << ": " << v2 << endl;
}
template <typename T1, typename T2, typename T3>
void dump_3(const string &n1, const T1 &v1, const string &n2, const T2 &v2,
            const string &n3, const T3 &v3) {
    cerr << n1 << ": " << v1 << "  " << n2 << ": " << v2 << "  " << n3 << ": "
         << v3 << endl;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &v) {
    os << "(" << v.first << ", " << v.second << ")";
    return os;
}
template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3> &v) {
    os << "(" << get<0>(v) << ", " << get<1>(v) << ", " << get<2>(v) << ")";
    return os;
}
template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
    os << "[";
    for (auto it = v.begin(); it != v.end(); it++) {
        if (it != v.begin()) {
            os << ", ";
        }
        os << *it;
    }
    os << "]";
    return os;
}
template <typename T> ostream &operator<<(ostream &os, const set<T> &v) {
    os << "{";
    for (auto it = v.begin(); it != v.end(); it++) {
        if (it != v.begin()) {
            os << ", ";
        }
        os << *it;
    }
    os << "}";
    return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const map<T1, T2> &v) {
    os << "{";
    for (auto it = v.begin(); it != v.end(); it++) {
        if (it != v.begin()) {
            os << ", ";
        }
        os << it->first << ":" << it->second;
    }
    os << "}";
    return os;
}
#endif // DEBUG
void Yes(void) { cout << "Yes" << endl; }
void No(void) { cout << "No" << endl; }
void YES(void) { cout << "YES" << endl; }
void NO(void) { cout << "NO" << endl; }
template <typename T> void print(const T &v) { cout << v << endl; }
//---------------------------------------------------------

ll divide2(ll h, ll w, ll s1) {
    ll h2 = h / 2;
    ll s2 = h2 * w;
    ll s3 = (h - h2) * w;
    ll ret1 = max({s1, s2, s3}) - min({s1, s2, s3});

    ll w2 = w / 2;
    s2 = h * w2;
    s3 = h * (w - w2);
    ll ret2 = max({s1, s2, s3}) - min({s1, s2, s3});
    return min(ret1, ret2);
}

ll divide3(ll h, ll w) {
    ll h3 = h / 3;
    ll s1 = h3 * w;

    ll ret1 = divide2(h - h3, w, s1);
    ll ret2 = INF;
    if (h3 < h) {
        h3++;
        s1 = h3 * w;
        ret2 = divide2(h - h3, w, s1);
    }

    ll w3 = w / 3;
    s1 = h * w3;
    ll ret3 = divide2(h, w - w3, s1);
    ll ret4 = INF;
    if (w3 < w) {
        w3++;
        s1 = h * w3;
        ret4 = divide2(h, w - w3, s1);
    }

    return min({ret1, ret2, ret3, ret4});
}

void solve() {
    ll H, W;
    cin >> H >> W;
    print(divide3(H, W));
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    solve();
}


Measured memory_bytes: 256