递归与循环

Posted 2020-12-31 jiaqi-666

实例1:斐波那契数列

# 1 1 2 3 5 8 13
# 计算n位的数vi
def fibo(n):
    if n <= 2:
        return 1
    return fibo(n - 1) + fibo(n - 2)

#计算比n小的最大数是数列中的第几位
print(fibo(n))
def func(m):
    n = 1
    while True:
        # if fibo(n) > m and fibo(n - 1) < m:
        if fibo(n + 1) > m >= fibo(n):
            return n
        else:
            n += 1

实例二:计算路径中总文件的大小

递归

# 用递归方法计算文件夹的大小
def cal_size(file_path):
    file_size = 0
    file_name = os.listdir(file_path)
    for name in file_name:
        name_path = os.path.join(file_path, name)
        if os.path.isdir(name_path):
            file_size += cal_size(name_path)
        else:
            file_size += os.path.getsize(name_path)
    return file_size


print(cal_size("H:GamePatch"))

循环方法:

lst = ["H:GamePatch", ]
file_size = 0
while lst:
    file_name = lst.pop()
    file_path = os.listdir(file_name)
    for name in file_path:
        name_new = os.path.join(file_name, name)
        if os.path.isdir(name_new):
            lst.append(name_new)
        else:
            file_size += os.path.getsize(name_new)
print(file_size)