Evaluating Mathematical Expressions

You are given a mathematical expression as a string. The expression can include non-negative numbers (which may contain decimal points), the operators \( + \), \( - \), \( \times \), and \( \div \), as well as parentheses \( ( \) and \( ) \). You must evaluate the expression and output the result as a floating point number.

Operator precedence follows standard mathematical conventions: Multiplication and division have higher precedence than addition and subtraction, and parentheses can be used to alter this precedence.

For example:

• Expression: 2+3 produces result 5.0.
• Expression: 2+3*4 produces result 14.0.
• Expression: 2*(3+4) produces result 14.0.

Implement a program that reads the expression from standard input (stdin) and writes the computed result to standard output (stdout).

inputFormat

The input consists of a single line containing the mathematical expression string. The expression may contain spaces.

Example:

 2 + 3 * ( 4 - 2 ) / 2 

outputFormat

Output the computed result as a floating point number. No extra spaces or lines should be printed.

Example:

5.0

## sample

2+3

5.0

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