Password Validator

Given a string s, determine if it is a valid password based on the following rules:

1. The password length must be between 8 and 20 characters, inclusive.
2. The password must contain at least one lowercase letter, one uppercase letter, one digit, and one special character from the set: !@#$%^&*()_+.
3. The password should not contain any whitespace characters (such as spaces or tabs).

If the password is valid, print VALID to the standard output; otherwise, print INVALID.

Mathematically, the conditions can be expressed as: \(8 \leq |s| \leq 20\) and \(s\ \text{contains at least one lowercase letter, one uppercase letter, one digit, and one special character from} \{!@#$%^&*()_+\}\) and \(s\ \text{contains no whitespace}\).

inputFormat

The input is provided via standard input as a single line containing the string s (the password to be validated).

outputFormat

Output VALID if the password meets the requirements, otherwise output INVALID. The output must be printed to the standard output.

## sample

Password123!

VALID

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