#include<bits/stdc++.h>
#include<algorithm>
#include<string>

using namespace std;


/*
    FILE *f=fopen("data.txt","w");
    fprintf(f,);
    fclose(f);
*/

#define FASTER ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define pi acos(-1.0)
#define scan(a) scanf("%d",&a)
#define scanll(a) scanf("%lld",&a)
#define print(a) printf("%d\n",a)
#define printll(a) printf("%lld\n",a)
#define stll(a) stoll(a,nullptr,10)
#define PII pair<ll,ll>
#define mp(a,b) make_pair(a,b)
#define EL printf("\n")
#define ff first
#define ss second

typedef long long ll;
typedef unsigned long long ull;

int main()
{
    ll n,sum=0,a;
    cin>>n;
    while(n--)
    {
        cin>>a;
        sum+=(a-1);
    }
    cout<<sum<<endl;
}




