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#include <bits/stdc++.h>
using namespace std;
const int N = 110;
int n, m;
int f[N][N];
int main() {
cin >> n >> m;
// 边界：第0次传球，第1个人获得球的机会数
f[0][1] = 1;
// 传m次球
for (int i = 1; i <= m; i++) {
for (int j = 1; j <= n; j++) {
if (j == 1)
f[i][j] = f[i - 1][j + 1] + f[i - 1][n];
else if (j == n)
f[i][j] = f[i - 1][j - 1] + f[i - 1][1];
else
f[i][j] = f[i - 1][j - 1] + f[i - 1][j + 1];
}
// 经过m次传球，球回到第1个人手中的机会数
cout << f[m][1] << endl;
return 0;
