Problem Statement

You are given $N$ positive integers $a_1, a_2, ..., a_N$.

For a non-negative integer $m$, let $f(m) = (m\ mod\ a_1) + (m\ mod\ a_2) + ... + (m\ mod\ a_N)$.

Here, $X\ mod\ Y$ denotes the remainder of the division of $X$ by $Y$.

Find the maximum value of $f$.

Constraints

• All values in input are integers.
• $2 \leq N \leq 3000$
• $2 \leq a_i \leq 10^5$

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

Print the maximum value of $f$.