regular expressions

The password is at least six characters long.

The password contains characters from at least three of the following
five categories:
· English uppercase characters (A - Z)
· English lowercase characters (a - z)
· Base 10 digits (0 - 9)
· Non-alphanumeric (for example: !, $, #, or %)
· Unicode characters

can u please help me in writing a regular expression for the above
condition

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