90分求调

#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
using namespace std;
int main(){
	int n,m,l,k;
	string b;
	vector<string> a,d;
	cin>>n>>m>>l;
	bool c = false;
	k = n+m+l;
	for(int i = 0;i < k;i++){
		cin>>b;
		a.push_back(b);
	}
	for(int i = 0;i < k;i++){
		for(int j = 0;j < k;j++){
			if(a[i] == a[j] && i != j){
				c = true;
				break;
			}
		}
		if(!c){
			d.push_back(a[i]);
		}
		c = false;
	}
	sort(d.begin(),d.end());
	for(int i = 0;i < d.size();i++){
		cout<<d[i]<<endl;
	}
	
	return 0;
}