delete pics to save space

7.1463.cpp

@@ -0,0 +1,50 @@
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+#include<vector>
+using namespace std;
+const int maxn=1505;
+const int oo=0x3f3f3f3f;
+int n,u,tot,v,f[maxn][2],vis[maxn][2];
+vector<int> G[maxn];
+int dfs(int u,int flg,int fa)
+{
+	int &res=f[u][flg];
+	if(vis[u][flg]) return res;
+	vis[u][flg]=1;
+	if(flg==1)
+	{
+		res=0;
+		for(int i=0;i<G[u].size();i++) if(G[u][i]!=fa) res+=min(dfs(G[u][i],1,u),dfs(G[u][i],0,u));
+		res++;
+	}
+	else
+	{
+		res=0;
+		for(int i=0;i<G[u].size();i++) if(G[u][i]!=fa) res+=dfs(G[u][i],1,u);
+	}
+	return res;
+}
+int main()
+{
+	#ifdef local
+	freopen("pro.in","r",stdin);
+	#endif
+	while(scanf("%d",&n)==1)
+	{
+		for(int i=0;i<n;i++) G[i].clear();
+		for(int i=0;i<n;i++)
+		{
+			scanf("%d:(%d)",&u,&tot);
+			for(int j=0;j<tot;j++)
+			{
+				scanf("%d",&v);
+				G[u].push_back(v);
+				G[v].push_back(u);
+			}
+		}
+		memset(vis,0,sizeof(vis));
+		printf("%d\n",min(dfs(0,1,-1),dfs(0,0,-1)));
+	}
+	return 0;
+}