#include<iostream>
#include<vector>
#include<queue>
using namespace std;
typedef pair<int, int >P;
queue<P> que;
vector<P> path;
const char* oprate[]={ "FILL(1)","FILL(2)","DROP(1)","DROP(2)","POUR(1,2)","POUR(2,1)" };
int used[1000][1000] = { 0 };
int a, b, c;
int i = -1;
void print(int p,int s) {
	if (p == 0) {
		cout << s << endl;
		return;
	}
	print(path[p].second,s+1);
	cout << oprate[path[p].first] << endl;
}
void bfs() {
	P p(0, 0);
	que.push(p);
	path.push_back(P(0, 0));
	bool flag = false;
	while (!que.empty()) {
		P cur = que.front();
		que.pop();
		i++;
		if (cur.first == c || cur.second == c) {
			flag = true;
			break;
		}
		if (!used[cur.first][cur.second]) {
			used[cur.first][cur.second] = 1;
			que.push(P(a, cur.second));
			path.push_back(P(0, i));

			que.push(P(cur.first, b));
			path.push_back(P(1, i));

			que.push(P(0, cur.second));
			path.push_back(P(2, i));

			que.push(P(cur.first, 0));
			path.push_back(P(3, i));

			que.push(P(max(cur.first - b + cur.second, 0), min(b, cur.second + cur.first)));
			path.push_back(P(4, i));

			que.push(P(min(a, cur.first + cur.second), max(cur.second - a + cur.first, 0)));
			path.push_back(P(5, i));
		}
	}
	if (flag) 
		print(i,0);
	else 
		cout << "impossible\n";
}
int main() {
	cin >> a >> b >> c;
	bfs();
	return 0;
}