11-p11_trains

def get_train(n,m=0):#n列车，m辆在里面等
    if n==0 :#边界
        return 1
    result=get_train(n-1,m+1)
    if m>0:
        result += get_train(n,m-1)#m-1
    return result


if __name__ == '__main__':
    for n in range(1,10+1):
        print(n,get_train(n))

D:\Anaconda\python.exe D:/AI20/06_codes/deeplearning_20/p11_trains.py
1 1
2 2
3 5
4 14
5 42
6 132
7 429
8 1430
9 4862
10 16796

Process finished with exit code 0