Problem Description

Assume an expression consists of lowercase English letters, operators (+, -, *, /), and left/right round parentheses, with @ as the terminator of the expression. Write a program to check whether the left and right parentheses in the expression are matched. If they match, output YES; otherwise, output NO. The expression length is less than $255$, and there are fewer than $20$ left parentheses.

Input Format

One line: the expression.

Output Format

One line: YES or NO.

2*(x+y)/(1-x)@

YES

(25+x)*(a*(a+b+b)@

NO

Hint

The expression length is less than $255$, and there are fewer than $20$ left parentheses.

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