#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <cctype>
#include <vector>
#include <map>
#include <set>
using namespace std;

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
const double EPS = 1e-9;

char temp[100];

void read(vector<pair<int, int> > & coins)
{
	double d;
	while (1)
	{
		scanf("%lf ", &d);
		if ((int)d == -1) break;
		scanf("%s ", temp);
		int len = strlen(temp);
		int num = 0;
		FOR(i, 0, len-1) num = num * 10 + temp[i] - '0';
		if (num)
			coins.push_back(make_pair((int)(d * 100.0 + EPS), num));
	}
}

int main()
{
	while (1)
	{
		double d;
		scanf("%lf ", &d);
		if ((int)d == -1) break;
		int target = d * 100.0 + EPS;

		vector<pair<int, int> > c1, c2;
		read(c1);
		read(c2);

		int m = 0;
		FOR(i, 0, c1.size()) m = max(m, c1[i].second);
		FOR(i, 0, c2.size()) m = max(m, c2[i].second);

		int res = -1;
		set<int> old, active;
		old.insert(0);
		FOR(step, 0, m+1)
		{
			for (set<int>::iterator iter = old.begin(); iter != old.end(); ++iter)
			{
			//cout << *iter << " ";
			FOR(i, 0, c1.size())
			{
				active.insert(*iter + c1[i].first);
				if (*iter + c1[i].first == target) res = step+1;
				if (--c1[i].second == 0)
					c1.erase(c1.begin() + i--);
			}
			FOR(i, 0, c2.size())
			{
				active.insert(*iter - c2[i].first);
				if (*iter - c2[i].first == target) res = step+1;
				if (--c2[i].second == 0)
					c2.erase(c2.begin() + i--);
			}
			}
			//cout << endl;
			if (res != -1) break;
			active.swap(old);
			active.clear();
		}
		if (res == -1) printf("The payment is impossible.\n");
		else printf("%d tenders must be exchanged.\n", res);
	}

	return 0;
}