delete pics to save space

1.3388.cpp

@@ -0,0 +1,48 @@
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+using namespace std;
+const int maxn=100005;
+struct Edge { int v; Edge *next; };
+Edge *G[maxn],mem[maxn*2],*ecnt=mem;
+void AddEdge(int u,int v) { ecnt->v=v; ecnt->next=G[u]; G[u]=ecnt++; }
+int n,m,x,y;
+int low[maxn],dfn[maxn],dfs_clock;
+bool iscut[maxn];
+int dfs(int u,int fa)
+{
+	int lowu=dfn[u]=++dfs_clock,child=0;
+	for(Edge *it=G[u];it;it=it->next)
+	{
+		int v=it->v;
+		if(!dfn[v])
+		{
+			++child;
+			int lowv=dfs(v,u);
+			lowu=min(lowu,lowv);
+			if(lowv>=dfn[u]) iscut[u]=true;
+		}
+		else if(dfn[v]<dfn[u]&&v!=fa) lowu=min(lowu,dfn[v]); 
+	}
+	if(fa<0&&child<=1) iscut[u]=false;
+	return lowu;
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d%d",&n,&m);
+	while(m-->0)
+	{
+		scanf("%d%d",&x,&y);
+		AddEdge(x,y); AddEdge(y,x);
+	}
+	for(int i=1;i<=n;i++) if(!dfn[i]) dfs(i,-1);
+	int sum=0;
+	for(int i=1;i<=n;i++) sum+=iscut[i];
+	printf("%d\n",sum);
+	for(int i=1;i<=n;i++) if(iscut[i]) printf("%d ",i);
+	printf("\n");
+	return 0;
+}