题解 | #走方格的方案数#

感觉是一个迭代啊

def func(x,y):
    if x < 0 or y < 0:
        return 0
    elif x == 0 or y == 0:
        return 1
    else:
        return func(x-1, y)+func(x, y-1)

while True:
    try:
        a,b = map(int,input().split())
        c = func(a, b)
        print(c)
    except:
        break