Here given a password, our task is to check that this Password is valid or not. Here we use re module that provide regular expression and re.search() is used for checking the validation of alphabets, digits or special characters.
Algorithm
Step 1: first we take an alphanumeric string as a password. Step 2: first check that this string should minimum 8 characters. Step 3: the alphabets must be between a-z. Step 4: At least one alphabet should be in Uppercase A-Z. Step 5: At least 1 number or digit between 0-9. Step 6: At least 1 character from [_ or @ or $].
Example Code
# Python program to check valid password import re passw = input("Enter Password ::>") fl = 0 while True: if (len(passw)<8): fl= -1 break elif not re.search("[a-z]", passw): fl = -1 break elif not re.search("[A-Z]", passw): fl = -1 break elif not re.search("[0-9]", passw): fl = -1 break elif not re.search("[_@$]", passw): fl = -1 break elif re.search("\s", passw): fl = -1 break else: fl = 0 print(" This Is Valid Password") break if fl ==-1: print("Not a Valid Password")
Output
Enter Password ::> vbnA@hj9 This Is Valid Password