#include <bits/stdc++.h>
using namespace std;
vector<int> adj[200010];
int dis[200010], dis2[200010], deg[200010], ans, par[200010], n;
bool isNear(int v) { return dis[v] <= 2 || dis2[v] <= 2; }
void makeNear(int v) {
  if (dis[v] <= 1) return;
  if (dis2[v] <= 1) return;
  dis2[v] = min(dis2[v], 1);
  for (auto u : adj[v]) dis2[u] = min(dis2[u], 2);
  ans++;
}
void dfs(int v, int f, int d) {
  dis[v] = d;
  par[v] = f;
  for (int i = 0; i < adj[v].size(); i++) {
    int u = adj[v][i];
    if (u != f) dfs(u, v, d + 1);
  }
}
void bfs() {
  vector<int> q;
  for (int i = 1; i <= n; i++) {
    if (deg[i] == 1) {
      q.push_back(i);
    }
  }
  for (int i = 0; i < q.size(); i++) {
    int v = q[i];
    int u = par[v];
    if (!isNear(v) && u != -1) {
      makeNear(u);
    }
    if (u != -1) {
      deg[u]--;
      deg[v]--;
      if (deg[u] == 1) {
        q.push_back(u);
      }
    }
  }
}
int main() {
  cin >> n;
  if (n == 1 || n == 2 || n == 3) {
    cout << 0 << endl;
  }
  for (int i = 0; i < n - 1; i++) {
    int x, y;
    cin >> x >> y;
    adj[x].push_back(y);
    adj[y].push_back(x);
    deg[x]++;
    deg[y]++;
  }
  for (int i = 1; i <= n; i++) {
    dis[i] = dis2[i] = 1e9;
    par[i] = -1;
  }
  dfs(1, -1, 0);
  bfs();
  cout << ans << endl;
}
