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 C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <iostream>
#include <vector>
#include <algorithm>
#include <numeric>

using namespace std;

typedef long long ll;

#define REP(var,n) for(int var=0;var<(n);var++)
#define REPP(var,n) for(int var=1;var<(n);var++)
#define ALL(c) (c).begin(),(c).end()

int main(){
    int N,i;
    cin >> N;

    int a[N];
    REP(i,N){
        cin >> a[i];
    }

    ll min_lcm = 1;

    REP(i,N){
        if(min_lcm % a[i] != 0){
            min_lcm = min_lcm*a[i];   
        }
    }

    min_lcm -= 1;

    int ans = 0;

    REP(i,N){
        ans += min_lcm % a[i];
    }

    cout << ans << endl;
}