#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>#include <string>#include <cmath>#include <cstdlib>#include <vector>#include <queue>#include <set>#include <map>using namespace std;const int maxn=11000;const int INF=1e6;struct Edge{int to,next;}edge[maxn*2];int Adj[maxn],Size;int dp[maxn][3],n;void init(){Size=0; for(int i=0;i<=n+10;i++){Adj[i]=-1;dp[i][0]=1; dp[i][1]=0; dp[i][2]=INF;}}void add_edge(int u,int v){edge[Size].to=v;edge[Size].next=Adj[u];Adj[u]=Size++;}void dfs(int u,int fa){for(int i=Adj[u];~i;i=edge[i].next){int v=edge[i].to;if(v==fa) continue;dfs(v,u);dp[u][0]+=min(dp[v][0],dp[v][1]);dp[u][1]+=dp[v][2];dp[u][2]=min(dp[u][2],dp[v][0]-dp[v][2]);}dp[u][2]+=dp[u][1];}int main(){while(scanf("%d",&n)!=EOF){if(n==-1) break;else if(n==0) continue;init();for(int i=0;i<n-1;i++){int a,b;scanf("%d%d",&a,&b);add_edge(a,b); add_edge(b,a);}dfs(1,0);printf("%dn",min(dp[1][0],dp[1][2]));} return 0;}
