View Code of Problem 2591

#include<bits/stdc++.h>
using namespace std;

int main() {

	int t;
	cin>>t;
	getchar();
	while(t--) {
		vector<char>v;
		string s1,s2;
		cin>>s1>>s2;
		for(int i=0; i<s1.length(); i++) {
			if(s2.find(s1[i])!=-1) {
				v.push_back(s1[i]);
				int k=s2.find(s1[i]);
				s2.erase(k,1);
			}

		}
		sort(v.begin(),v.end());
		if(v.size()==0) {
			cout<<-1<<endl;
		} else {
			for(int i=0; i<v.size(); i++) {
				cout<<v[i];
			}
			cout<<endl;
		}

	}
	return 0;
}