题意：两个整数集合 合并，并且从大到小输出

#include<iostream>
#include<cstdio>
#include<set>
using namespace std;
set<int>str;
int n, m;
int c;
int main()
{
    int a;
    while (cin >> n >> m)
    {
        c = 0;
        str.clear();
        while (n--)
        {
            cin >> a;
            if (str.find(a) == str.end())
            {
                str.insert(a);
                c++;
            }
        }
        while (m--)
        {
            cin >> a;
            if (str.find(a) == str.end())
            {
                str.insert(a);
                c++;
            }
        }
        int cc = 0;
        for (set<int>::iterator it = str.begin(); it != str.end(); ++it)
        {
            cout << *it ;
            cc++;
            if (cc != c)
            {
                cout << " ";
            }
        }
        cout << endl;
    }
    return 0;
}