#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 sz(v) (int)v.size() #define inf (int)(1e9+7) #define INF (ll)(1e18) #define abs(x) (x >= 0 ? x : -(x)) #define ceil(a, b) a / b + !!(a % b) template inline bool chmin(T1 &a, T2 b) { if (a > b) { a = b; return 1; } return 0; } template inline bool chmax(T1 &a, T2 b) { if (a < b) { a = b; return 1; } return 0; } template T gcd(T a, T b) { if (b == 0) return a; return gcd(b, a % b); } int main() { int n; cin >> n; vector a(n), b(n); rep(i, n) cin >> a[i] >> b[i]; set s; rep(i, n) s.insert(a[i]); set used; rep(i, n) { if (!s.count(b[i]) && !used.count(b[i])) { cout << b[i] << endl; used.insert(b[i]); } } }