#include <bits/stdc++.h>
using namespace std;

const int MOD = 1000000007;

// begin() end()
#define all(x) (x).begin(),(x).end()

#define REP(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)

//最大公約数 
unsigned gcd(unsigned a, unsigned b) {
  if(a < b) return gcd(b, a);
  unsigned r;
  while ((r=a%b)) {
    a = b;
    b = r;
  }
  return b;
}

//最小公倍数
int lcm(int number1,int number2){
	return number1 * number2 / gcd(number1,number2);	
}
  
int main(){
int N;
cin >> N;

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

int sum = 0;
REP(i,N){
    sum += a[i] - 1;
}

cout << aum << endl; 
}