#include <bits/stdc++.h>
using namespace std;
int n, m;
struct Edge {
  int to, next;
} e[200010 * 2];
int c1, head[200010];
inline void add_edge(int u, int v) {
  e[c1].to = v;
  e[c1].next = head[u];
  head[u] = c1++;
}
int dep[200010], f[200010];
void dfs(int u, int fa) {
  for (int i = head[u]; ~i; i = e[i].next) {
    int v = e[i].to;
    if (v == fa) continue;
    dep[v] = dep[u] + 1;
    f[v] = u;
    dfs(v, u);
  }
}
int id[200010];
bool vis[200010];
int main() {
  fill(head, head + 200010, -1);
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  cin >> n;
  for (int i = 1; i < n; ++i) {
    int x, y;
    cin >> x >> y;
    add_edge(x, y);
    add_edge(y, x);
  }
  dep[1] = 1;
  dfs(1, 0);
  for (int i = 1; i <= n; ++i) id[i] = i;
  sort(id + 1, id + n + 1,
       [](const int &u, const int &v) { return dep[u] > dep[v]; });
  int ans = 0;
  for (int i = 1, u = id[1]; i <= n && dep[u] > 3; u = id[++i]) {
    if (vis[u]) continue;
    ++ans;
    vis[f[u]] = 1;
    for (int i = head[f[u]]; ~i; i = e[i].next) {
      int v = e[i].to;
      vis[v] = 1;
    }
  }
  cout << ans << "\n";
  return 0;
}
