496

Using set::set_intersect(params) the problem can be solved.

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <set>
#include <algorithm>
#include <sstream>

#define INF 1000000
using namespace std;

set<int> Set1,Set2,inn;
int main()
{
	int n;
	string str;
	stringstream ss;
	while(getline(cin,str))
	{
		Set1.clear();
		Set2.clear();
		inn.clear();

		ss.clear();
		ss<<str;
		while(ss>>n)
		{
			Set1.insert(n);
		}

		getline(cin,str);
		ss.clear();
		ss<<str;
		while(ss>>n)
		{
			Set2.insert(n);
		}

		set_intersection(Set1.begin(),Set1.end(),Set2.begin(),Set2.end(),insert_iterator< set<int> >(inn,inn.begin()));

		if(Set1==Set2)
		cout<<"A equals B\n";
		else if(Set2==inn)
		cout<<"B is a proper subset of A\n";
		else if(Set1==inn)
		cout<<"A is a proper subset of B\n";
		else if(inn.size()==0)
		cout<<"A and B are disjoint\n";
		else
		cout<<"I'm confused!\n";
	}
	return 0;
}