delete pics to save space

2.1267.cpp

@@ -0,0 +1,71 @@
+#include<cstdio>
+#include<cstring>
+#include<vector>
+#include<algorithm>
+using namespace std;
+const int maxn=1010;
+vector<int> gr[maxn],nodes[maxn];
+int T,n,s,k,fa[maxn];
+bool vis[maxn];
+void build(int u,int f,int d)
+{
+	fa[u]=f;
+	int nc=gr[u].size();
+	if(nc==1&&d>k) nodes[d].push_back(u);
+	for(int i=0;i<nc;i++)
+	{
+		int v=gr[u][i];
+		if(v!=f) build(v,u,d+1);
+	}
+}
+int dfs(int u,int f,int d)
+{
+	vis[u]=true;
+	int nc=gr[u].size();
+	for(int i=0;i<nc;i++)
+	{
+		int v=gr[u][i];
+		if(v!=f&&d<k) dfs(v,u,d+1);
+	}
+}
+int cal()
+{
+	int res=0;
+	memset(vis,0,sizeof(vis));
+	for(int d=n-1;d>k;d--)
+	{
+		int nc=nodes[d].size();
+		for(int i=0;i<nc;i++)
+		{
+			int u=nodes[d][i];
+			if(vis[u]) continue;
+			int v=u;
+			for(int j=0;j<k;j++) v=fa[v];
+			dfs(v,-1,0);
+			res++;
+		}
+	}
+	return res;
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d",&T);
+	while(T-->0)
+	{
+		scanf("%d%d%d",&n,&s,&k);
+		for(int i=1;i<=n;i++) { gr[i].clear(); nodes[i].clear(); }
+		for(int i=0;i<n-1;i++)
+		{
+			int a,b;
+			scanf("%d%d",&a,&b);
+			gr[a].push_back(b);
+			gr[b].push_back(a);
+		}
+		build(s,-1,0);
+		printf("%d\n",cal());
+	}
+	return 0;
+}