Problem:
Score : 300 points

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.

Sample Input 1

3
3 4 6

Sample Output 1

10

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

Sample Input 2

5
7 46 11 20 11

Sample Output 2

90

Sample Input 3

7
994 518 941 851 647 2 581

Sample Output 3

4527

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = Integer.parseInt(in.nextLine());
		String[] tokens = in.nextLine().split(" ");
		int a[] = new int[n];
		for (int i = 0; i < n; ++i) {
			a[i] = Integer.parseInt(tokens[i]);
		}
		in.close();

		System.out.println(getVal(a, conv(a) * 2 - 1));
	}

	private static long conv(int[] in) {
		Set<Integer> set = new HashSet<>();
		for (int i : in) {
			set.add(i);
		}
		long result = 1;
		for (Integer i : set) {
			result *= i;
		}
		return result;

	}

	private static long getVal(int[] inputs, long x) {
		long result = 0;
		for (int input : inputs) {
			result += x % input;
		}
		return result;
	}
}