#include using namespace std; typedef long long ll; #define F first #define S second #define pii pair #define eb emplace_back #define all(v) v.begin(), v.end() #define rep(i, n) for (int i = 0; i < n; ++i) #define rep3(i, l, n) for (int i = l; i < n; ++i) #define chmax(a, b) a = (a >= b ? a : b) #define chmin(a, b) a = (a <= b ? a : b) #define out(a) cout << a << endl #define outa(a, n) rep(_, n) cout << a[_] << " "; cout << endl #define SZ(v) (int)v.size() #define inf (int)(1e9+7) #define abs(x) (x >= 0 ? x : -(x)) int main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin >> n; cin.ignore(); string s; getline(cin, s); // out(SZ(s)); if (regex_search(s, regex(" "))) { out("assert"); return 0; } ll a = stoi(s); ll b, c; cin >> b >> c; vector v; v.eb(a + b); v.eb(b + c); v.eb(c + a); sort(all(v)); if (v[0] == v[1] && v[1] == v[2]) out("assert"); else if (v[2] == v[1]) out(v[0]); else out(v[1]); }