Daily Challenge #300 - Username / Password Comparison

dev.to staff - Oct 29 '20 - - Dev Community

You are writing a password validator for a website. You want to discourage users from using their username as part of their password, or vice-versa, because it is insecure. Since its unreasonable to not allow them to have any letters in common, you come up with this rule:

For any password and username pair, the length of the longest common substring should be less than half the length of the shortest of the two.

In other words, you won't allow users to have half their password repeated in their username, or half their username repeated in their password.

Write a function validate(username, password) which returns true if your rule is followed, false otherwise.

Assume both the username and the password may contain uppercase letters, lowercase letters, numbers, spaces, and the following special/punctation characters: !@#$%^&*()_+{}:"<>?[];',. The username and password will each be less than 100 characters.

Examples

validate("newyorkcity", "yankees101"), TRUE
validate("username", "usernamePW"), FALSE

Tests

validate("Paa2", "Paaaaaa222!!!")
validate("wordpass", "password")
validate("superman", "persuzod")


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