//#include #include // cout, endl, cin #include // string, to_string, stoi #include // vector #include // min, max, swap, sort, reverse, lower_bound, upper_bound #include // pair, make_pair #include // tuple, make_tuple #include // int64_t, int*_t #include // printf #include // map #include // queue, priority_queue #include // set #include // stack #include // deque #include // unordered_map #include // unordered_set #include // bitset #include // isupper, islower, isdigit, toupper, tolower #include #include using namespace std; typedef long long ll; typedef unsigned long long ull; typedef long double ld; #define rep(i,n) for(int i = 0; i < (n); i++) #define pb push_back #define eb emplace_back #define all(x) x.begin() , x.end() #define fi frist #define se second #define Yes() {puts("YES");return;} #define No() {puts("No"); return;} #define P pair #define vi vector #define vvi vector<> #define vs vector #define vll vector const int INF = 1001001001; const int mod = 1000000007; const ld PI = 3.14159265358979; ll gcd (ll a , ll b) { if (a < b) swap(a , b); if (b == 0) return 1; if (a % b == 0) return b; else return gcd (b , a % b); } bool is_prime (ll x) { if (x == 1) { return false; } if (x == 2 || x == 3 || x == 5 || x == 7) { return true; } if((x & 1) == 0){ return false; } for (ll i = 3; i * i <= x; i += 2) { if(x % i == 0)return false; } return true; } bool is_2power(ll x) { if((x & (x - 1)) == 0) { return true; } else { return false; } } vector divisor (ll x) { vector ret; for (int i = 2; i * i <= x; i++) { while (x % i == 0) { ret.push_back(i); x /= i; } } if (x > 1) { ret.push_back(x); } return ret; } ll modpow (ll x , ll p , ll m) { ll ret = 1; while (p > 0) { if(p & 1)ret *= x; x *= x; x %= m; p >>= 1; } return ret; } int func(ld x){ string s = to_string(x); int ret = 0; for (int i = 0; i < s.size(); i++) { ret += s[i] - '0'; } return ret; } int main(void){ cin.tie(0); ios::sync_with_stdio(false); //cout << fixed << setprecision(15); int n; cin >> n; vll a(n); const ll MOD = 9; rep(i,n)cin >> a[i]; ll ans = 0; rep(i,n){ ans += a[i]; ans %= MOD; } cout << ans << endl; return 0; }