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: Accepted)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

  public static void main(String[] args) {
    new Main().run();
  }

  public void run() {
    
    try(BufferedReader in = new BufferedReader(new InputStreamReader(System.in))) {

      int n = Integer.parseInt(in.readLine());
      String line = in.readLine();
      int sum = 0;
      
      int offset=0,next=0;
      char regex = ' ';
      for(int i=0; i<n; i++) {
        if((next = line.indexOf(regex,offset)) == -1)
          next = line.length();
        sum += Integer.parseInt(line.substring(offset, next));
        offset = ++next;
      }

      System.out.println(sum-n);
    }
    catch(IOException e) {
      System.err.println(e);
    }
  }
}