#include #define F first #define S second #define MP make_pair #define pb push_back #define endl '\n' using namespace std; typedef long long LL; typedef pair< int, int > P; typedef pair< LL, LL > LP; typedef pair< int, P > iP; typedef pair< P, P > PP; static const int INF = INT_MAX; static const LL LINF = LLONG_MAX; static const int MIN = INT_MIN; static const LL LMIN = LLONG_MIN; static const int MOD = 1000000007; int dx[] = {0, -1, 1, 0}; int dy[] = {-1, 0, 0, 1}; vector< int > v[100005]; int main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin >> n; for( int i = 0; i < n - 1; ++i ) { int a, b; cin >> a >> b; v[a].pb( b ); v[b].pb( a ); } int o_cnt = 0; //次数1のノードをカウント int more_cnt = 0; //次数3以上のノードをカウント for( int i = 1; i <= n; ++i ) { if( o_cnt < 2 && v[i].size() == 1 ) { ++o_cnt; for( int j = 0; j < v[i].size(); ++i ) { if( v[j].size() >= 3 ) v[j].pop_back(); } } else if( v[i].size() == 1 || v[i].size() >= 3 ){ ++more_cnt; } } cout << more_cnt << endl; return 0; }