#include <cstdio>#include <cstdlib>#include <cstring>#include <climits>#include <cctype>#include <cmath>#include <string>#include <sstream>#include <iostream>#include <algorithm>#include <iomanip>using namespace std;#include <queue>#include <stack>#include <vector>#include <deque>#include <set>#include <map>typedef long long LL;#pragma comment(linker, "/STACK:1024000000,1024000000")#define pi acos(-1.0)#define lson l, m, rt<<1#define rson m+1, r, rt<<1|1typedef pair<int, int> PI;typedef pair<int, PI> PP;int orz[30];char s[441];int main(){ int n,m,t; while(scanf("%d%d%d",&n,&m,&t)!=EOF) { memset(orz,0,sizeof(orz)); for(int i=0;i<n;i++){ scanf("%s",s); for(int j=0;j<m;j++) orz[s[j]-'A']++;}for(int i=0;i<t;i++){ scanf("%s",s); int len=strlen(s); for(int j=0;j<len;j++) orz[s[j]-'A']--;}for(int i=0;i<26;i++){ if(orz[i]>0) while(orz[i]--) printf("%c",'A'+i);}printf("n"); } return 0;}
