#include<iostream>
#include<string>
#include<cstring>
#include<algorithm>
#include<vector>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#define MAXA 100000
#define MAX 20000000000
#define s(i) scanf("%d", &(i))
#define p(i) printf("%d", (i))
#define ps() printf(" ") 
#define rer(i,j,k) for((i)=(j);(i)<(k);++(i))
#define ret(i,j,k) for((i)=(j);(i)>(k);--(i))
using namespace std;


int main(){
	int i, sum = 0, m;
	cin >> n;
	rer(i,0,n){
		cin >> m;
		sum += (m-1);
	}
	cout << sum << endl;
	
	return 0;
}