#include <bits/stdc++.h>
#include <random>
using namespace std; typedef unsigned long long _ulong; typedef long long int lint; typedef pair<lint, lint> plint; typedef pair<double long, double long> pld;
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((lint)(x).size())
#define FOR(i, begin, end) for(lint i=(begin),i##_end_=(end);i<i##_end_;++i)
#define IFOR(i, begin, end) for(lint i=(end)-1,i##_begin_=(begin);i>=i##_begin_;--i)
#define REP(i, n) FOR(i,0,n)
#define IREP(i, n) IFOR(i,0,n)
#define endk '\n'
#define fi first
#define se second
struct fast_ios { fast_ios() { cin.tie(nullptr), ios::sync_with_stdio(false), cout << fixed << setprecision(20); }; } fast_ios_;
template<class T> auto add = [](T a, T b) -> T { return a + b; };
template<class T> auto f_max = [](T a, T b) -> T { return max(a, b); };
template<class T> auto f_min = [](T a, T b) -> T { return min(a, b); };
template<class T> using V = vector<T>;
using Vl = V<lint>; using VVl = V<Vl>;
template< typename T > ostream& operator<<(ostream& os, const vector< T >& v) {
	for (int i = 0; i < (int)v.size(); i++) os << v[i] << (i + 1 != v.size() ? " " : "");
	return os;
}
template< typename T >istream& operator>>(istream& is, vector< T >& v) {
	for (T& in : v) is >> in;
	return is;
}
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return 1; } return 0; }
lint gcd(lint a, lint b) { if (b == 0) return a; else return gcd(b, a % b); }
lint ceil(lint a, lint b) { return (a + b - 1) / b; }
lint digit(lint a) { return (lint)log10(a); }
lint e_dist(plint a, plint b) { return abs(a.fi - b.fi) * abs(a.fi - b.fi) + abs(a.se - b.se) * abs(a.se - b.se); }
lint m_dist(plint a, plint b) { return abs(a.fi - b.fi) + abs(a.se - b.se); }
void Worshall_Floyd(VVl& g) { REP(k, SZ(g)) REP(i, SZ(g)) REP(j, SZ(g)) chmin(g[i][j], g[i][k] + g[k][j]); }
const lint MOD = 1e9 + 7, INF = 1e9 + 1;
lint dx[8] = { 1, 0, -1, 0, 1, -1, 1, -1 }, dy[8] = { 0, 1, 0, -1, -1, -1, 1, 1 };
bool YN(bool flag) { cout << (flag ? "YES" : "NO") << endk; return flag; } bool yn(bool flag) { cout << (flag ? "Yes" : "No") << endk; return flag; }
struct Edge {
	lint from, to;
	lint cost;
	Edge(lint u, lint v, lint c) {
		cost = c;
		from = u;
		to = v;
	}
	bool operator<(const Edge& e) const {
		return cost < e.cost;
	}
};
struct WeightedEdge {
	lint to;
	lint cost;
	WeightedEdge(lint v, lint c = 1) {
		to = v;
		cost = c;
	}
	bool operator<(const WeightedEdge& e) const {
		return cost < e.cost;
	}
};
using WeightedGraph = V<V<WeightedEdge>>;
typedef pair<lint, plint> tlint;
typedef pair<plint, plint> qlint;
typedef pair<string, lint> valstring;


template <std::int_fast64_t Modulus>
class modint
{
	using u64 = std::int_fast64_t;

public:
	u64 a;
	constexpr modint(const u64 x = 0) noexcept : a(x% Modulus) {}
	constexpr u64& value() noexcept { return a; }
	constexpr const u64& value() const noexcept { return a; }
	constexpr modint operator+(const modint rhs) const noexcept
	{
		return modint(*this) += rhs;
	}
	constexpr modint operator-(const modint rhs) const noexcept
	{
		return modint(*this) -= rhs;
	}
	constexpr modint operator*(const modint rhs) const noexcept
	{
		return modint(*this) *= rhs;
	}
	constexpr modint operator/(const modint rhs) const noexcept
	{
		return modint(*this) /= rhs;
	}
	constexpr modint& operator+=(const modint rhs) noexcept
	{
		a += rhs.a;
		if (a >= Modulus)
		{
			a -= Modulus;
		}
		return *this;
	}
	constexpr modint& operator-=(const modint rhs) noexcept
	{
		if (a < rhs.a)
		{
			a += Modulus;
		}
		a -= rhs.a;
		return *this;
	}
	constexpr modint& operator*=(const modint rhs) noexcept
	{
		a = a * rhs.a % Modulus;
		return *this;
	}
	constexpr modint& operator/=(modint rhs) noexcept
	{
		u64 exp = Modulus - 2;
		while (exp)
		{
			if (exp % 2)
			{
				*this *= rhs;
			}
			rhs *= rhs;
			exp /= 2;
		}
		return *this;
	}
};
typedef modint<MOD> ModInt;

ModInt mod_pow(ModInt x, lint n) {
	ModInt ret = 1;
	while (n > 0) {
		if (n & 1) (ret *= x);
		(x *= x);
		n >>= 1;
	}
	return ret;
}

ModInt func[200000];
void funcinit(int N)
{
	func[0] = 1;
	for (int i = 1; i <= N; i++)
	{
		func[i] = func[i - 1] * i;
	}
}
ModInt comb(ModInt n, ModInt r)
{
	if (n.a <= 0 || n.a < r.a)
	{
		return 1;
	}
	return func[n.a] / (func[r.a] * func[(n - r).a]);
}

struct Topological_Sort {
public:

	Topological_Sort(int _n) : G(_n, Vl()), indegree(_n, 0), N(_n) {}

	void add_edge(int u, int v) {
		G[u].push_back(v);
		indegree[v]++;
	}

	Vl get() {
		Vl sorted_vertices;
		Vl tmp_indegree = indegree;
		queue<int> que;
		REP(i, N) {
			if (tmp_indegree[i] == 0) que.push(i);
		}

		while (!que.empty()) {
			int v = que.front(); que.pop();
			REP(i, SZ(G[v])) {
				int u = G[v][i];
				tmp_indegree[u]--;
				if (tmp_indegree[u] == 0) que.push(u);
			}
			sorted_vertices.push_back(v);
		}

		return sorted_vertices;
	}
private:
	VVl G;
	Vl indegree;
	int N;
};

lint N, M, u, v, l, a;
int main() {
	cin >> N >> M;
	VVl to(N + 1, Vl());
	V<V<tlint>> rev(N + 1, V<tlint>());
	Topological_Sort topo(N + 1);
	REP(i, M) {
		cin >> u >> v >> l >> a;
		topo.add_edge(u, v);
		rev[v].push_back({ u, {l, a} });
	}
	auto vec = topo.get();
	if (SZ(vec) != N + 1) {
		cout << "INF" << endk;
	}
	else {
		reverse(ALL(vec));
		V<ModInt> dp(N + 1);
		for (lint v : vec) {
			for (auto nxt : rev[v]) {
				dp[nxt.first] += (dp[v] + nxt.second.first) * nxt.second.second;
			}
		}
		cout << dp[vec.back()].a << endk;
	}
}