#include <algorithm>
#include <cstdlib>
#include <iostream>
#include <unordered_map>
#include <utility>
#include <vector>
using namespace std;

class union_find {
private:
	vector<int> uf;

public:
	union_find(int n):uf(n, -1) {}

	inline int find(int x) {
		return uf[x] < 0 ? x : uf[x] = find(uf[x]);
	}

	inline void unite(int x, int y) {
		x = find(x);
		y = find(y);
		if(x == y)
			return;

		if(uf[x] > uf[y])
			swap(x, y);

		else if(uf[x] == uf[y])
			--uf[x];

		uf[y] = x;
	}

	inline bool same(int x, int y) {
		return find(x) == find(y);
	}
};

struct edge {
	int a, b, cost;
	edge(int a, int b, int cost):a(a), b(b), cost(cost) {}
};

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	constexpr long long mod = 10007;

	for(int n; cin >> n && n;) {
		vector<edge> es;
		es.reserve(n);

		for(int i = 0; i < n; ++i) {
			for(int j = 0; j < 2; ++j) {
				int to, cost;
				cin >> to >> cost;
				if(to < i) continue;
				es.emplace_back(i, to, cost);
			}
		}

		union_find uf(n);
		for(int i = 0; i < n; ++i) {
			uf.unite(es[i].a, es[i].b);
		}

		unordered_map<int, pair<int, int>> num;

		for(int i = 0; i < n; ++i) {
			const int group_id = uf.find(es[i].a);
			pair<int, int>& tmp = num[group_id];

			if(tmp.first < es[i].cost) {
				tmp = make_pair(es[i].cost, 1);
			}
			else if(tmp.first == es[i].cost) {
				++tmp.second;
			}
		}

		long long ans = 1;
		for(const auto& element : num) {
			ans *= element.second.second;
			ans %= mod;
		}

		cout << ans << endl;
	}

	return EXIT_SUCCESS;
}