#include<fstream>
#include<deque>
using namespace std;
class xy
{
public:
	int x,y;
};
int main()
{
	ifstream fi("horse.in");
	ofstream fo("horse.out");
	deque<xy> lj;
	xy mm,nn;
	int m,n,s=0,qd[4][2]={{-2,1},{-1,2},{1,2},{2,1}};
	fi>>m>>n;
	mm.x=1;
	mm.y=1;
	lj.push_back(mm);
	while(!lj.empty())
	{
		mm=lj.front();
		lj.pop_front();
		for(int i=0;i<=3;i++)
		{
			nn=mm;
			nn.x+=qd[i][0];
			nn.y+=qd[i][1];
			if(nn.x<=m&&nn.x>=1&&nn.y<=n)
				if(nn.x==m&&nn.y==n)
					s++;
				else
					lj.push_back(nn);
		}
	}
	fo<<s<<endl;
	fi.close();
	fo.close();
	return 0;
}