#include<cstdio>#include<cstring>#include<algorithm>#include<vector>#include<set>#include<map>using namespace std;const int maxn=100010;const int INF=100000;set<int> sample,single;int table[maxn];vector<int> s;int main(){	fill(table,table+maxn,INF);	int n;	scanf("%d",&n);	int a,b,temp;	for(int i=0;i<n;i++)	{		scanf("%d%d",&a,&b);		table[a]=b;		table[b]=a;	}	int m;	scanf("%d",&m);	for(int i=0;i<m;i++)	{		scanf("%d",&a);		single.insert(a);	}	for(set<int>::iterator it=single.begin();it!=single.end();it++)	{		if(single.find(table[*it])!=single.end())		{			continue;		}		else			s.push_back(*it);	}	PRintf("%d/n",s.size());	for(vector<int>::iterator it=s.begin();it!=s.end();it++)	{		if(it!=s.begin()) printf(" ");			printf("%05d",*it);		}	system("pause");	return 0;}