隊列、棧和遞歸遍歷目錄

時間 2020-01-07

原文原文鏈接

棧

棧是一種內存結構，先進後出，後進先出。python中沒有棧的概念，咱們目前只能仿寫。python

# 模擬棧結構
stack = []
# 入棧（添加元素）
stack.append("A")
print(stack)
stack.append("B")
print(stack)
stack.append("C")
print(stack)
#入棧順序 A B C

# 出棧（移除元素）
stack.pop()
print(stack)
stack.pop()
print(stack)
#出棧順序 C B A

隊列

隊列也是一種內存結構，先進先出，後進後出。app

建立隊列

import collections
queue = collections.deque()

# 進隊（向隊列中添加元素）
queue.append("A")
queue.append("B")
queue.append("C")
print(queue)
# 出隊（移除隊列中的元素）
queue.popleft()
print(queue)
queue.popleft()
print(queue)

遞歸遍歷目錄和文件

import os

path = r'F:\PycharmProjects\basic gram\做業和習題\test'

def getAllFileAndDir(path):
    # 獲取當前目錄下全部文件及文件目錄
    fileList = os.listdir(path)
    # print(fileList)

    # 遍歷fileList列表
    for fileName in fileList:
        # isdir isfile
        # print(fileName)
        # 拼接絕對路徑
        absFile = os.path.join(path,fileName)
        if os.path.isdir(absFile):
            print(absFile+'---目錄')
            getAllFileAndDir(absFile)
        else:
            print(absFile+'---文件')    
getAllFileAndDir(path)

棧深度遍歷

import collections

def getAllFileAndDir(sourcePath):

    stack = collections.deque()
    stack.append(sourcePath)
    while len(stack) != 0:
        path = stack.pop()
        fileList = os.listdir(path)
        for fileName in fileList:
            absFile = os.path.join(path, fileName)
            if os.path.isdir(absFile):
                print(absFile+'---目錄')
                stack.append(absFile)
            else:
                print(absFile+'---文件')

getAllFileAndDir(path)

隊列廣度遍歷

def getAllFileAndDir(sourcePath):

    queue = collections.deque()
    queue.append(sourcePath)

    while len(queue) !=0:
        path = queue.popleft()
        fileList = os.listdir(path)
        for fileName in fileList:
            absFile = os.path.join(path, fileName)
            if os.path.isdir(absFile):
                print(absFile+'---目錄')
                queue.append(absFile)
            else:
                print(absFile+'---文件')


getAllFileAndDir(path)

複製目錄和文件

import os
# 複製目錄
def copyDir(sourDir,targetDir):
    if not os.path.exists(sourDir):
        print("若是源目錄不存在,直接中止")
        return

    if not os.path.exists(targetDir):
        os.makedirs(targetDir)

    listName = os.listdir(sourDir)
    for dirNameAndFileName in listName:
        sourAbsPath = os.path.join(sourDir,dirNameAndFileName)
        targetAbsPath = os.path.join(targetDir,dirNameAndFileName)
        if os.path.isdir(sourAbsPath):
            copyDir(sourAbsPath,targetAbsPath)
        if os.path.isfile(sourAbsPath):
            #   若是目標文件不存在,   或者   若是該文件已經存在可是文件大小不同
            if (not os.path.exists(targetAbsPath)) or (os.path.exists(targetAbsPath) and (os.path.getsize(sourAbsPath) != os.path.getsize(targetAbsPath))):
                rf = open(sourAbsPath,"rb")
                wf = open(targetAbsPath,"wb")
                while True:
                    content = rf.read(1024*1024)
                    if len(content) == 0:
                        break
                    wf.write(content)
                    wf.flush()
                wf.close()
                rf.close()

sPath = r'F:\PycharmProjects\basic gram\做業和習題\test'
tPath = r'F:\PycharmProjects\basic gram\做業和習題\testNew'
copyDir(sPath, tPath)

文件複製實例

1.一個函數接受文件夾的名稱做爲輸入參數,請將該文件夾中的全部文件複製到文件夾名-副本中去,請補充缺失的代碼. (20分)
def copyFile(sPath)
2.題1複製過程當中,每隔一秒打印一次複製進度(即當前已複製個數/總文件個數)(15分)

import os
import collections
import time
import sys
def getFileNum(sPath):
    num = 0
    stack = collections.deque()
    stack.append(sPath)
    while len(stack) != 0:
        path = stack.pop()
        fileList = os.listdir(path)
        for fileName in fileList:
            absFile = os.path.join(path, fileName)
            if os.path.isdir(absFile):
                stack.append(absFile)
            else:
                num += 1
    return num

def copyFile(sPath):
    tPath = r'F:\PycharmProjects\basic gram\做業和習題\Anaconda3-副本'
    stack1 = collections.deque()
    stack1.append(sPath)
    stack2 = collections.deque()
    stack2.append(tPath)
    timepoint = 1
    filenum = 0
    while len(stack1) != 0:
        sPath = stack1.pop()
        tPath = stack2.pop()
        if not os.path.exists(tPath):
            os.makedirs(tPath)
        listName = os.listdir(sPath)
        for filename in listName:
            absfile = os.path.join(sPath, filename)
            tabsfile = os.path.join(tPath, filename)
            if os.path.isdir(absfile):
                stack1.append(absfile)
                stack2.append(tabsfile)
            else:
                rf = open(absfile, 'rb')
                wf = open(tabsfile, 'wb')
                while True:
                    content = rf.read(1024*1024)
                    if len(content) == 0:
                        break
                    wf.write(content)
                    # 刷新緩衝區
                    wf.flush()
                    if time.clock()//1 == timepoint:
                         sys.stdout.write('\r進度:%d/%d'%(filenum,num))
                         timepoint += 1
                wf.close()
                rf.close()
                filenum += 1
    sys.stdout.write('\r進度:%d/%d' % (num, num))


sPath = r'F:\PycharmProjects\basic gram\做業和習題\Anaconda3'

num = getFileNum(sPath)
# print(num)
start_time = time.clock()
copyFile(sPath)