如何讓這個程序更快（更高效）？

Question

我有這個代碼，它使用文件中每個單詞的第一個字母創建唯一的密碼。在每個密碼創建（寫入文件）之前，它將與當前在文件中的所有密碼進行比較，因此如果文件具有在寫入另一個密碼之前需要50,000個密碼，它必須掃描所有50k。 用戶可以輸入任意數量的密碼，但數字越大需要花費的時間越長，需要很長時間我如何優化這個以使程序運行更快？口令產生不包括代碼

for mainLoop in range(passnum): 

     user = 0 
     newpass = generatePassword() # New password generated each iteration of loop 
     storePass = open("MnemPass.txt","a") 
     print ("PASSWORD GENERATED ") 

     #Checks if file is empty if True write first password 
     fileEmpty = os.stat("MnemPass.txt").st_size == 0 
     if fileEmpty == True: 
      storePass.write(newpass) 
      storePass.write("\n") 
      storePass.close() 
      print ("FIRST PASSWORD WRITTEN") 

     #IF file is not empty Read line by line and compare each with new password generated returns boolean value 
     elif fileEmpty == False: 
      storePass = open("MnemPass.txt","r") 
      with open("MnemPass.txt") as f: 
       fileData = f.read().splitlines() 
       linelength = len(fileData).__int__() 
       filemax = linelength 
       num = linelength #Number used to cycle through array set to size of list 
       #print(linelength+10) 

       for iterate in range(linelength): 
        num = num - 1 #Number decreases each pass 
        #print num 
        if fileData[num] != newpass: # The last element in the array is checked first decrementing each pass 
         go = True 

        if fileData[num]==newpass: #changed 
         print ("match found: PASSWORD : "+fileData[num]) 
         passMatch = open("Matchpassword.txt","a") 
         passMatch.write(newpass) 
         passMatch.write("\n") 
         passMatch.close() 
         go = False 
         break 

        #places new password once it does not match and all elements prev passwords are compared 
        if go == True and num == 0: 
         storePass = open("MnemPass.txt","a") 
         storePass.write(newpass) 
         storePass.write("\n") 
         storePass.close() 
         print ("NEW WRITTEN") 



      if linelength == filemax: 

       num = num -1 

*新的代碼 - 我使用的設定功能*

 passnum = (input("How many passwords do you need :")) 
    sTime = datetime.now()
 

storePass = open ("MnemPass.txt","a") # file open out of loop to increase speed 
    fileEmpty = os.stat("MnemPass.txt").st_size == 0
 

new_passwords = set() 
    CurrentPasswords = set()
 

if fileEmpty == True: 
    while len(new_passwords)!= passnum: #will cause problems if dictionary cannot create amount needed 
      new_passwords.add(generatePassword())
 

for pw in new_passwords: 
     storePass.write(pw + "\n") 
 

其他：開放（「MnemPass.txt線路
new_passwords =集（line.strip（） 「））
有效範圍內的NUM（passnum）：
溫度= generatePassword（）
 

 if temp not in new_passwords: 
      CurrentPasswords.add(temp) 
     else: 
      "match found" 

爲PW2在CurrentPasswords： storePass.write（對W2 +「\ n」）

Answer 1

在，你在這裏提出您的代碼在循環運行的情況： 檢查在每次循環迭代整個文件是不是很有效。 保存一組創建的密碼並在添加新密碼之前檢查新密碼是否已經存在，會更有效率。 同樣在這種情況下，您應該只在主for循環外打開一次文件，然後關閉它。

如果您的程序只添加一個密碼然後返回，最好以您的文件保持排序的方式添加每個新密碼。這樣，您可以使用二進制搜索來搜索密碼是否已經存在。

Answer 2

你可以通過加載文件一次，然後附加每個新的密碼，而不是循環打開文件並逐行檢查，從而大大減少運行時間，這裏我使用uuid在generatePassword()產生一個長度在3和10

您的代碼：

def func(passnum): 
    import os,uuid,random 
    def generatePassword(): 
     return str(uuid.uuid4()).replace('-', '')[0:random.randint(3,10)] 
    for mainLoop in range(passnum): 

      user = 0 
      newpass = generatePassword() # New password generated each iteration of loop 
      storePass = open("MnemPass.txt","a") 
      print ("PASSWORD GENERATED ") 

      #Checks if file is empty if True write first password 
      fileEmpty = os.stat("MnemPass.txt").st_size == 0 
      if fileEmpty == True: 
       storePass.write(newpass) 
       storePass.write("\n") 
       storePass.close() 
       print ("FIRST PASSWORD WRITTEN") 

      #IF file is not empty Read line by line and compare each with new password generated returns boolean value 
      elif fileEmpty == False: 
       storePass = open("MnemPass.txt","r") 
       with open("MnemPass.txt") as f: 
        fileData = f.read().splitlines() 
        linelength = len(fileData).__int__() 
        filemax = linelength 
        num = linelength #Number used to cycle through array set to size of list 
        #print(linelength+10) 

        for iterate in range(linelength): 
         num = num - 1 #Number decreases each pass 
         #print num 
         if fileData[num] != newpass: # The last element in the array is checked first decrementing each pass 
          go = True 

         if fileData[num]==newpass: #changed 
          print ("match found: PASSWORD : "+fileData[num]) 
          passMatch = open("Matchpassword.txt","a") 
          passMatch.write(newpass) 
          passMatch.write("\n") 
          passMatch.close() 
          go = False 
          break 

         #places new password once it does not match and all elements prev passwords are compared 
         if go == True and num == 0: 
          storePass = open("MnemPass.txt","a") 
          storePass.write(newpass) 
          storePass.write("\n") 
          storePass.close() 
          print ("NEW WRITTEN") 



       if linelength == filemax: 

        num = num -1 

我稍微修改它加載該文件在啓動本身並追加爲每一個新的密碼，我們並不需要爲內部循環不再另行通知，代碼變成：

def func2(passnum): 
    import uuid 
    import os, random 
    linelength = 0 
    fileData = [] 
    if os.path.isfile('MnemPass.txt'): 
     f = open("MnemPass.txt", "r") 
     fileData += f.read().splitlines() 
     linelength = len(fileData).__int__() 
     f.close() 

    def generatePassword(): 
     return str(uuid.uuid4()).replace('-', '')[0:random.randint(3,10)] 

    for mainLoop in range(passnum): 

     user = 0 
     newpass = generatePassword() # New password generated each iteration of loop 
     storePass = open("MnemPass.txt", "a") 
     print ("PASSWORD GENERATED ") 

     # Checks if file is empty if True write first password 
     fileEmpty = os.stat("MnemPass.txt").st_size == 0 
     if fileEmpty == True: 
      storePass.write(newpass) 
      storePass.write("\n") 
      storePass.close() 
      print ("FIRST PASSWORD WRITTEN") 

     # IF file is not empty Read line by line and compare each with new password generated returns boolean value 
     elif fileEmpty == False: 
      storePass = open("MnemPass.txt", "r") 
      filemax = linelength 
      num = linelength # Number used to cycle through array set to size of list 
      # print(linelength+10) 

      if newpass in fileData: 
        print ("match found: PASSWORD : " , fileData.index(newpass)) 
        passMatch = open("Matchpassword.txt", "a") 
        passMatch.write(newpass) 
        passMatch.write("\n") 
        passMatch.close() 
      else: 
        linelength += 1 
        fileData.append(newpass) 
        storePass = open("MnemPass.txt", "a") 
        storePass.write(newpass) 
        storePass.write("\n") 
        storePass.close() 
        print ("NEW WRITTEN") 
      if linelength == filemax: 
       num = num - 1 

個人資料代碼：

個人資料修改後的代碼：

正如你所看到的運行時間已經從45secs減少到27secs！:)

注：

我跑了10000個密碼測試並刪除生成的文件的下一次:)