#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define all(c) c.begin(), c.end() #define rall(c) c.rbegin(), c.rend() #define debug(x) cerr << #x << ": " << x << endl using namespace std; typedef long long ll; typedef pair Pll; typedef pair Pii; const ll MOD = 1000000007; const long double EPS = 1e-10; const int dyx[4][2] = { { 0, 1}, {-1, 0}, {0,-1}, {1, 0} }; int main() { std::ios::sync_with_stdio(0); cin.tie(0); int n, a, b; cin >> n; vector degrees(n, 0); for(int i=0;i> a >> b; ++degrees[a-1]; ++degrees[b-1]; } cout << count(all(degrees), 1) - 2 << endl; }