Evaluate Simple Arithmetic Expression

You are given a string representing a simple mathematical expression which contains non-negative integers and the operators $$+$$ and $$-$$. The expression is written without any spaces. Evaluate the expression from left to right and output the result.

For instance, given the expression 12+34-5+67, the expected result is 108.

inputFormat

A single line containing the arithmetic expression. The expression consists only of non-negative integers and the operators + and -.

outputFormat

A single line that outputs the result of the evaluated expression as an integer.## sample

1+2

3