题解 | #走方格的方案数#

# -*-coding:utf-8-*-

while True:
    try:
        n,m =  map(int,input().split(" "))
        x=0
        dp = [[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):
                dp[i][j] = dp[i-1][j]+dp[i][j-1]
        x = dp[m][n]
        print(x)
    except:
        break