#include #define FOR(i, a, b) for (int i = (a); i < (b); i++) #define RFOR(i, a, b) for (int i = (b)-1; i >= (a); i--) #define rep(i, n) for (int i = 0; i < (n); i++) #define rep1(i, n) for (int i = 1; i <= (n); i++) #define rrep(i, n) for (int i = (n)-1; i >= 0; i--) #define pb push_back #define mp make_pair #define fst first #define snd second #define show(x) cout << #x << " = " << x << endl #define chmin(x, y) x = min(x, y) #define chmax(x, y) x = max(x, y) #define pii pair #define vi vector using namespace std; template ostream& operator<<(ostream& o, const pair& p) { return o << "(" << p.first << "," << p.second << ")"; } template ostream& operator<<(ostream& o, const vector& vc) { o << "sz = " << vc.size() << endl << "["; for (const T& v : vc) o << v << ","; o << "]"; return o; } using ll = long long; constexpr ll MOD = 1000000007; constexpr int MAX = 100000; constexpr int LOG = 30; bool bits[MAX][LOG]; bool rest[LOG]; void decode(ll a, int n) { int i = 0; while (a > 0) { bits[n][i] = (a % 2); a /= 2; i++; } } int main() { int N; cin >> N; rep(i, N) { ll a; cin >> a; decode(a, i); } rep(i, LOG) { bool c[2] = {false, false}; rep(j, N) { c[bits[j][i]] = true; } if (c[0] and c[1]) { rest[i] = true; } else { rest[i] = false; } } ll m = 0; ll p = 1; rep(i, LOG) { if (rest[i]) { m += p * (ll)rest[i]; } p *= 2; } cout << m << endl; return 0; }