let str;
while(str = readline()) {
    let arr1 = readline().split(' ').map(Number);
    let str2 = readline();
    let arr2 = readline().split(' ').map(Number);
    let res = [...new Set([...arr1,...arr2])];
    res.sort((a,b)=>a-b);
    console.log(res.join(''));
}