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.

-----Sample Input-----
3
3 4 6

-----Sample Output-----
10

f(11) = (11\ mod\ 3) + (11\ mod\ 4) + (11\ mod\ 6) = 10 is the maximum value of f.

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