题解 | #走方格的方案数#

n, m = map(int, input().split())

if 1 <= n <= 8 and 1 <= m <= 8 :
    nm = [[1 for i in range(n+1)] for j in range(m+1)]
    for i in range(1,m+1):
      for j in range(1,n+1):
          nm[i][j] = nm[i-1][j] + nm[i][j-1]
    print(nm[-1][-1])
else:print("n或m越界")