枚举中间的数+dp
dp[0] = dp[1] = 1;
for(int i=2;i<=1000;i++)
{
	dp[i] = 0;
	if(i%2==0) dp[i]+=dp[i/2];
	for(int j=1;j<=i;j++)
	{
		int temp = i - j;
		if(temp%2==0) dp[i] += dp[temp/2];
	}
}