传球游戏

#include <bits/stdc++.h>
using namespace std;
int main(void)
{
int i,j, n,m;
cin >> n >> m;
long long a[40][40] = {0};
a[0][1] = 1;
a[0][n + 1] = 1;
for (int i = 1;i <= m;i++)
{
for (int j = 1;j <= n + 1;j++)
{
a[i][j] = a[i - 1][j - 1] + a[i - 1][j + 1];
}
a[i][1] = a[i][n + 1] = a[i][1] + a[i][n + 1];
}
printf("%d\n",a[m][1]);
return 0;
}