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: Accepted)

#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>
#define int long long
#define endl '\n'
#define null nullptr
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(), x.rend()
#define pb push_back
#define mp make_pair
#define test int t; cin>>t; while(t--)
#define FAST                          \
    ios_base::sync_with_stdio(false); \
    cin.tie(NULL);                    \
    cout.tie(NULL)

using namespace std;

typedef vector<int> vi;
typedef vector<pair<int,int>> vii;
typedef pair<int,int> pii;
typedef unordered_map<int,int> mp;

const int mod = 1e9+7;



int32_t main(){
    FAST;

    int n;  cin >> n;
        int ans = 0;
    for(int x=0;x<n;x++){
        int t;  cin >> t;
        ans += t;

    }

    cout << (ans - n);

    return 0;
}