Evaluate Mathematical Expression

You are given a non-empty string representing a mathematical expression. The expression contains non-negative integers, the operators +, -, *, /, and parentheses ( ). Evaluate the expression following the standard operator precedence rules and using left-to-right associativity. Note that the division operator performs integer division (i.e. it truncates toward zero).

For example, the expression 3 + 2 * 2 evaluates to 7, and the expression (2+6)/2 evaluates to 4.

The expression is guaranteed to be valid.

inputFormat

The input consists of a single line containing a non-empty string s that represents a mathematical expression. The string may include spaces.

outputFormat

Output a single integer representing the evaluated result of the expression.

3+2*2

7