#include #define FOR(i,a,b) for(int i = (a); i < (b); ++i) #define REP(i,n) FOR(i,0,n) #define SZ(n) (int)(n).size() #define ALL(n) (n).begin(), (n).end() using namespace std; typedef long long LL; typedef vector VI; int main() { int n; cin >> n; LL a; LL sum = 0; REP(i, n) { cin >> a; sum += a; } cout << sum - a << endl; return 0; }