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 Pascal (FPC 2.6.2) (judge verdict: Accepted)

program Project1;
     
{$APPTYPE CONSOLE}
     
uses
  SysUtils;
var
  a,h,w,i,j,count,count2,x,y,sw,m,n,b,c,soeji,sum,max,k:Integer;
  l:array of Integer;
  s,s123,s1,s2,s3:string;
  al:string = 'abcdefghijklmnopqrstuvwxyz';
  tf,tfl,tfr:Boolean;
begin
  try
    { TODO -oUser -cConsole メイン : ここにコードを記述してください }
    Readln(a);
    sum:=0;
    for I := 0 to a - 1 do begin
      Read(b);
      sum:=sum+b;
    end;

    Writeln(sum-a);
    Readln;
    Readln;
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
end.