Python脚本016：查找两个不同文件夹中是否存在相同文件

#coding:utf-8
import os
import hashlib  #hash函数
import shutil

def makesDir(filepath): #判断如果文件不存在,则创建
    if not os.path.exists(filepath):
        os.makedirs(filepath)

if __name__ == '__main__':
    A=r'/home/jy/xl/workstation/Datasets/Car/Nighttime_Vehicle_ReID/Query'#代表是目录A
    B=r'/home/jy/xl/workstation/Datasets/Car/Nighttime_Vehicle_ReID/Gallery' #代表是目录B
    C=r'/home/jy/xl/workstation/Datasets/Car/Nighttime_Vehicle_ReID/Same' #代表是目录A和目录B的差集放在目录C
    makesDir(C)
    md5dict={}
    for filename in os.listdir(A):#返回的是一个一个的文件名
        hashvalue=hashlib.md5(filename.encode( 'utf-8' )).hexdigest()
        md5dict[hashvalue]=os.path.join(A, filename)
    for filename in os.listdir(B):
        hashvalue=hashlib. md5(filename.encode( 'utf-8' )).hexdigest()
        if hashvalue in md5dict:
            shutil.copy(os.path. join(B, filename),os.path.join(C,filename))

用hash查找，速度真的好快，