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#include 
#include 
#include 
#include 
#include 
#include 
#include 
using namespace std;
typedef long long ll;
const int maxn = 2e5 + 10;
const int logn = 20;
vector graph[maxn];
bool visited[maxn];
int res;
void dfs(int node, int prev) {
    for(int i = 0; i < (int) graph[node].size(); i++) {
        int neigh = graph[node][i];
        if(neigh != prev) {
            dfs(neigh, node);
            if(!visited[neigh] and !visited[node]) {
                visited[neigh] = true;
                visited[node] = true;
                ++res;
            }
        }
    }
}
int main() {
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n;
    for(int i = 1; i < n; i++) {
        int a, b;
        cin >> a >> b;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }
    res = 0;
    memset(visited, 0, sizeof visited);
    dfs(1, -1);
    cout << res << endl;
    return 0;
}

// 200000