Rearrange Digits to Validate Expression

You are given a mathematical expression in the format LHS=RHS where both sides may contain digits and the operators + and -. The challenge is to determine whether it is possible to rearrange the digits (while keeping the operators and the locations of non‐digit characters fixed) such that the resulting expression becomes a valid equality. More formally, if we denote the original expression as

\( \texttt{expr} = E_1 = E_2 \),

you must check if there exists a permutation of all digit characters in \(E_1\) and \(E_2\) that can be reinserted in place of the original digits so that

\( \texttt{eval}(E_1') = \texttt{eval}(E_2') \)

where \(E_1'\) and \(E_2'\) are the expressions after substitution and \(\texttt{eval}(\cdot)\) represents the evaluation of the arithmetic expression. Output YES if such a rearrangement exists, otherwise output NO.

Note: The expressions will only contain non-negative integers, plus ('+') and minus ('-') operators, and exactly one '=' symbol.

inputFormat

The input consists of a single line containing the expression string. There are no extra spaces in the input.

Example:

2+2=4

outputFormat

For the given expression, output a single line: YES if a valid rearrangement exists that makes the equality true, or NO otherwise.

Example:

YES

## sample

2+2=4

YES