Evaluate Mathematical Expression

You are given a mathematical expression as a string. The expression contains non-negative integers, operators +, -, *, /, ^ (exponentiation) and parentheses. The operator ^ stands for exponentiation and should be treated with the highest precedence. Use integer division for the division operator. Your task is to evaluate the expression and output its integer result.

Note: The expression is guaranteed to be valid. Operands may have multiple digits and spaces may appear arbitrarily in the expression.

inputFormat

The input consists of a single line that contains the arithmetic expression. For example:

3 + 2 * (2 - 1)

outputFormat

Output a single integer which is the result of evaluating the expression. For instance, the above input should produce:

5

## sample

3

3

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