#include<iostream>
#include<cstring>
#include<string>
#include<cstdio>
#include<iomanip>
#include<cstdlib>
#include<stdlib.h>
#include<cmath>
#include<algorithm>
#include<vector>
#include<map>
#include<stack>
#include<queue>
#include<deque>
using namespace std;
long long n,m,total;
void dfs(long long x,long long y){
	if(x==n&&y==m){
		total++;
		return;
	}
	if(x>n||y>m||x<0||y<0){
		return;
	}	
	dfs(x+1,y-2);
	dfs(x+2,y-1);
	dfs(x+1,y+2);
	dfs(x+2,y+1);
}
int main(){
	cin>>n>>m;
	dfs(0,0);
	cout<<total<<"\n";
	return 0;
}