Python递归函数的规律

'''
需求：计算n! = 1 * 2 * 3 * .... * n
1.临界条件：n = 1
2.关系：n - 1
3.求出最后结果： n * (n - 1)
'''
def jiecheng(n): # n = 5  n = 4
    if n == 1: # 临界条件
        return 1
    else:
        return jiecheng(n - 1) * n # jiecheng(4) * 5  jiecheng(3) * 4 * 5

print(jiecheng(5))