#include<bits/stdc++.h>
using namespace std;using ll=long long;using vi=vector<int>;using vvi=vector<vi>;using vl=vector<ll>;using vvl=vector<vl>;using P=pair<int,int>;using PL=pair<ll,ll>;using vp=vector<P>;using vpl=vector<PL>;
template<typename T>constexpr auto inf=numeric_limits<T>::max()/2;constexpr int INF=inf<int>,MOD=1000000007;constexpr ll LINF=inf<ll>;
#define _ol3(_1,_2,_3,name,...)name
#define _rep(i,n)_repi(i,0,n)
#define _repi(i,a,b)for(int i=a,i##_l=(b);i<i##_l;++i)
#define REP(...)_ol3(__VA_ARGS__,_repi,_rep,)(__VA_ARGS__)
#define REPR(i,n)for(int i=n-1;i>=0;--i)
#define REPA(i,v)REP(i,v.size())
#define all(v)(v).begin(),(v).end()
#define bit(n)(1ll<<(n))
#define uniq(v)sort(all(v));v.erase(unique(all(v)),v.end())
#define F first
#define S second
#define endl '\n'
#define cho(n,a,b)cout<<((n)?a:b)<<endl
void YES(int n){cho(n,"YES","NO");}void Yes(int n){cho(n,"Yes","No");}void Poss(int n){cho(n,"Possible","Impossible");}
void _print(ostream&s){}template<class T,class...U>void _print(ostream&s,T&&t,U&&...u){s<<t<<(sizeof...(u)?' ':'\n');_print(s,u...);}
template<class...T>void print(T&&...t){_print(cout,t...);}
#ifndef LOCAL
struct osd{template<class T>osd&operator<<(const T&t){return*this;}};osd cer_;
#define dprint(...)
#define cerr cer_
#else
template<class...T>void dprint(T&&...t){_print(cerr,t...);}
#endif
template<class T>void chmax(T&a,const T&b){if(a<b)a=b;}template<class T>void chmin(T&a,const T&b){if(a>b)a=b;}
template<class T>ostream&operator<<(ostream&o,const vector<T>&v){for(auto&&i:v)o<<i<<' ';return o;}
template<class T>istream&operator>>(istream&i,vector<T>&v){for(T&j:v)i>>j;return i;}
template<class T,class U>ostream&operator<<(ostream&o,const pair<T,U>&p){return o<<p.F<<' '<<p.S;}
template<class T,class U>istream&operator>>(istream&i,pair<T,U>&p){return i>>p.F>>p.S;}
template<class T>ostream&operator<<(ostream&o,const set<T>&v){for(auto&&i:v)o<<i<<' ';return o;}
template<class T>ostream&operator<<(ostream&o,const multiset<T>&v){for(auto&&i:v)o<<i<<' ';return o;}
template<class T>vector<T>&operator<<(vector<T>&v,const T&t){v.push_back(t);return v;}
template<class T>set<T>&operator<<(set<T>&v,const T&t){v.insert(t);return v;}
template<class T>multiset<T>&operator<<(multiset<T>&v,const T&t){v.insert(t);return v;}

inline ll mami(ll a,ll b,ll c){return max({a,b,c})-min({a,b,c});}

ll split2(ll a,ll b, ll h) {
    ll mi=INF;
    chmin(mi, mami(a/2*h, a/2*h+a%2*h, b*h));
    chmin(mi, mami(h/2*a, h/2*a+h%2*a, b*h));
    chmin(mi, mami(b/2*h, b/2*h+b%2*h, a*h));
    chmin(mi, mami(h/2*b, h/2*b+h%2*b, a*h));
    return mi;
}
ll split1(ll h,ll w){
    ll mi=INF;
    switch(h%3){
        case 0:
            chmin(mi, split2(h/3, h/3*2, w));
            break;
        case 1:
            chmin(mi, split2(h/3  , h/3*2+1, w));
            chmin(mi, split2(h/3+1, h/3*2, w));
            break;
        case 2:
            chmin(mi, split2(h/3+2, h/3*2  , w));
            chmin(mi, split2(h/3+1, h/3*2+1, w));
            chmin(mi, split2(h/3  , h/3*2+2, w));
            break;
    }
    return mi;
}

int main(){
    cin.tie(0);ios::sync_with_stdio(0);
    ll h,w;
    cin>>h>>w;
    cout<<min(split1(h,w), split1(w,h))<<endl;
    return 0;
}


Measured memory_bytes: 256