Unique Characters Checker

You are given a string S consisting of lowercase English letters. Determine whether every character in the string is unique, i.e., no character appears more than once.

If S has all unique characters, print True. Otherwise, print False.

Note: For an empty string, consider it as having all unique characters.

The problem can be mathematically stated as follows:

Given a string \( S \), verify if \( |S| = |\{c : c \in S\}| \). If the equality holds, output True; otherwise, output False.

inputFormat

The input consists of a single line containing the string S.

Constraints:

• S contains only lowercase letters ('a'-'z').
• The length of S is in a reasonable limit to process (e.g., up to 10⁵ characters).

outputFormat

Output a single line: True if every character in S is unique, or False otherwise.

## sample

abcdef

True