View Code of Problem 2591

#include<iostream>
#include<stdio.h> 
#include<algorithm>
using namespace std;
int main(){
	int t;
	cin>>t;
	string a,b;
	while(t--){
		cin>>a>>b;
		char c[999];
		int flag=0,k=0;
		int l1=a.length(),l2=b.length();		
		for(int i=0;i<l1;i++){
			for(int j=0;j<l2;j++){
				if(a[i]==b[j]){
					c[k++]=a[i];
					b[j]='*';
					flag=1;
					break;
				}
			}
		}
		
		if(flag==0)cout<<"-1";
		else{
			sort(c,c+k);
			
			for(int i=0;i<k;i++){
				cout<<c[i];
			} 
		}
		cout<<endl; 
		
	} 
	return 0;
}