import core.bitop;
import std.algorithm;
import std.ascii;
import std.bigint;
import std.conv;
import std.functional;
import std.format;
import std.math;
import std.numeric;
import std.range;
import std.stdio;
import std.string;
import std.random;
import std.typecons;

alias sread = () => readln.chomp();
alias Point2 = Tuple!(long, "y", long, "x");

T lread(T = long)()
{
    return readln.chomp.to!T();
}

T[] aryread(T = long)()
{
    return readln.split.to!(T[])();
}

void scan(TList...)(ref TList Args)
{
    auto line = readln.split();
    foreach (i, T; TList)
    {
        T val = line[i].to!(T);
        Args[i] = val;
    }
}

enum MOD = (10 ^^ 9) + 7;

void main()
{
    long H, W;
    scan(H, W);
    if (H % 3 == 0 || W % 3 == 0)
    {
        writeln(0);
        return;
    }
    long solve(long A, long B)
    {
        long ans = long.max;
        foreach (a; 1 .. A)
        {
            long S1 = a * B;
            long S2 = (A - a) * (B / 2);
            long S3 = (A - a) * ((B + 1) / 2);
            long tmp = max(S1, S2, S3) - min(S1, S2, S3);
            // writefln("%d %d %d %d", S1, S2, S3, tmp);
            ans = ans.min(tmp);
        }
        return ans;
    }

    long a3 = H * (W % 3);
    long a4 = W * (H % 3);

    min(solve(H, W), solve(W, H), a3, a4).writeln();
}
