A point-of-sale device records each receipt adjustment as a flat formula: a sequence of tokens alternating value, operator, value, operator, ... , value. Each value is an integer literal (it may be negative, e.g. -7; a negative literal always has more than one character, so it is never confused with the operator token -). Each operator is one of the single characters +, -, *, /.

Evaluate the formula strictly left to right with no operator precedence at all: apply each operator to the running result and the next value, in order. For example 2 + 3 * 4 is evaluated as (2 + 3) * 4 = 20, not 2 + 12. Division truncates toward zero (like integer division in C or Java), so -7 / 2 is -3.

It is guaranteed the token count is odd (values and operators alternate, starting and ending with a value) and that division by zero never occurs.

Input format

Line 1: an integer n, the number of tokens. Line 2: n space-separated tokens.

Output format

A single integer: the value of the formula.

Constraints

• 1 <= n <= 99 (odd)
• Each integer literal has absolute value <= 1000000.
• Division by zero never occurs.
• Every intermediate result and the final value fit in a signed 64-bit integer.

5
2 + 3 * 4

20

1
7

7