// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using ld = long double;
using pll = pair<ll, ll>;
using pii = pair<int, int>;
using vvl = vector<vector<ll>>;
using vvi = vector<vector<int>>;
using vvpll = vector<vector<pll>>;
#define rep(i, a, b) for (ll i=(a); i<(b); i++)
#define rrep(i, a, b) for (ll i=(a); i>(b); i--)
#define pb push_back
#define tostr to_string
#define ALL(A) A.begin(), A.end()
#define elif else if
// constexpr ll INF = LONG_LONG_MAX;
constexpr ll INF = 1e18;
constexpr ll MOD = 1000000007;

const string digits = "0123456789";
const string ascii_lowercase = "abcdefghijklmnopqrstuvwxyz";
const string ascii_uppercase = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string ascii_letters = ascii_lowercase + ascii_uppercase;

template<typename T> vector<vector<T>> list2d(int N, int M, T init) { return vector<vector<T>>(N, vector<T>(M, init)); }
template<typename T> vector<vector<vector<T>>> list3d(int N, int M, int L, T init) { return vector<vector<vector<T>>>(N, vector<vector<T>>(M, vector<T>(L, init))); }
template<typename T> vector<vector<vector<vector<T>>>> list4d(int N, int M, int L, int O, T init) { return vector<vector<vector<vector<T>>>>(N, vector<vector<vector<T>>>(M, vector<vector<T>>(L, vector<T>(O, init)))); }

vector<ll> LIST(ll N) { vector<ll> A(N); rep(i, 0, N) cin >> A[i]; return A; }

void print(ld out) { cout << fixed << setprecision(15) << out << '\n'; }
void print(double out) { cout << fixed << setprecision(15) << out << '\n'; }
template<typename T> void print(T out) { cout << out << '\n'; }
template<typename T1, typename T2> void print(pair<T1, T2> out) { cout << out.first << ' ' << out.second << '\n'; }
template<typename T> void print(vector<T> A) { rep(i, 0, A.size()) { cout << A[i]; cout << (i == A.size()-1 ? '\n' : ' '); } }
template<typename T> void print(set<T> S) { vector<T> A(S.begin(), S.end()); print(A); }

void Yes() { print("Yes"); }
void No() { print("No"); }
void YES() { print("YES"); }
void NO() { print("NO"); }

ll floor(ll a, ll b) { if (a < 0) { return (a-b+1) / b; } else { return a / b; } }
ll ceil(ll a, ll b) { if (a >= 0) { return (a+b-1) / b; } else { return a / b; } }
pll divmod(ll a, ll b) { ll d = a / b; ll m = a % b; return {d, m}; }
template<typename T> bool chmax(T &x, T y) { return (y > x) ? x = y, true : false; }
template<typename T> bool chmin(T &x, T y) { return (y < x) ? x = y, true : false; }

template<typename T> T sum(vector<T> A) { T res = 0; for (T a: A) res += a; return res; }
template<typename T> T max(vector<T> A) { return *max_element(ALL(A)); }
template<typename T> T min(vector<T> A) { return *min_element(ALL(A)); }

ll toint(string s) { ll res = 0; for (char c : s) { res *= 10; res += (c - '0'); } return res; }
int toint(char num) { return num - '0'; }
char tochar(int num) { return '0' + num; }
int ord(char c) { return (int)c; }
char chr(int a) { return (char)a; }

ll pow(ll x, ll n) { ll res = 1; rep(_, 0, n) res *= x; return res; }
ll pow(ll x, ll n, int mod) { ll res = 1; while (n > 0) { if (n & 1) { res = (res * x) % mod; } x = (x * x) % mod; n >>= 1; } return res; }

int popcount(ll S) { return __builtin_popcountll(S); }
ll gcd(ll a, ll b) { return __gcd(a, b); }
ll lcm(ll x, ll y) { return (x * y) / gcd(x, y); }

template<typename T> int bisect_left(vector<T> &A, T val) { return lower_bound(ALL(A), val) - A.begin(); }
template<typename T> int bisect_right(vector<T> &A, T val) { return upper_bound(ALL(A), val) - A.begin(); }

#include <algorithm>
#include <cassert>
#include <limits>
#include <queue>
#include <vector>
#include <algorithm>
#include <utility>
#include <vector>
namespace atcoder {
namespace internal {
template <class E> struct csr {
    std::vector<int> start;
    std::vector<E> elist;
    csr(int n, const std::vector<std::pair<int, E>>& edges)
        : start(n + 1), elist(edges.size()) {
        for (auto e : edges) {
            start[e.first + 1]++;
        }
        for (int i = 1; i <= n; i++) {
            start[i] += start[i - 1];
        }
        auto counter = start;
        for (auto e : edges) {
            elist[counter[e.first]++] = e.second;
        }
    }
};
}  // namespace internal
}  // namespace atcoder
#include <algorithm>
#include <cassert>
#include <vector>
#include <algorithm>
#include <utility>
#include <vector>
namespace atcoder {
namespace internal {
struct scc_graph {
  public:
    scc_graph(int n) : _n(n) {}
    int num_vertices() { return _n; }
    void add_edge(int from, int to) { edges.push_back({from, {to}}); }
    std::pair<int, std::vector<int>> scc_ids() {
        auto g = csr<edge>(_n, edges);
        int now_ord = 0, group_num = 0;
        std::vector<int> visited, low(_n), ord(_n, -1), ids(_n);
        visited.reserve(_n);
        auto dfs = [&](auto self, int v) -> void {
            low[v] = ord[v] = now_ord++;
            visited.push_back(v);
            for (int i = g.start[v]; i < g.start[v + 1]; i++) {
                auto to = g.elist[i].to;
                if (ord[to] == -1) {
                    self(self, to);
                    low[v] = std::min(low[v], low[to]);
                } else {
                    low[v] = std::min(low[v], ord[to]);
                }
            }
            if (low[v] == ord[v]) {
                while (true) {
                    int u = visited.back();
                    visited.pop_back();
                    ord[u] = _n;
                    ids[u] = group_num;
                    if (u == v) break;
                }
                group_num++;
            }
        };
        for (int i = 0; i < _n; i++) {
            if (ord[i] == -1) dfs(dfs, i);
        }
        for (auto& x : ids) {
            x = group_num - 1 - x;
        }
        return {group_num, ids};
    }
    std::vector<std::vector<int>> scc() {
        auto ids = scc_ids();
        int group_num = ids.first;
        std::vector<int> counts(group_num);
        for (auto x : ids.second) counts[x]++;
        std::vector<std::vector<int>> groups(ids.first);
        for (int i = 0; i < group_num; i++) {
            groups[i].reserve(counts[i]);
        }
        for (int i = 0; i < _n; i++) {
            groups[ids.second[i]].push_back(i);
        }
        return groups;
    }
  private:
    int _n;
    struct edge {
        int to;
    };
    std::vector<std::pair<int, edge>> edges;
};
}  // namespace internal
}  // namespace atcoder
namespace atcoder {
struct scc_graph {
  public:
    scc_graph() : internal(0) {}
    scc_graph(int n) : internal(n) {}
    void add_edge(int from, int to) {
        int n = internal.num_vertices();
        assert(0 <= from && from < n);
        assert(0 <= to && to < n);
        internal.add_edge(from, to);
    }
    std::vector<std::vector<int>> scc() { return internal.scc(); }
  private:
    internal::scc_graph internal;
};
}  // namespace atcoder
using namespace atcoder;

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

    ll N, M;
    cin >> N >> M;
    N++;
    vvpll nodes(N);
    scc_graph scc(N);
    rep(i, 0, M) {
        ll u, v, l, a;
        cin >> u >> v >> l >> a;
        nodes[u].pb({v, l*a});
        scc.add_edge(u, v);
    }

    auto res = scc.scc();
    vector<int> ts;
    for (auto &group : res) {
        bool has_0, has_n, is_cycle;
        if (group.size() >= 2) is_cycle = 1;
        for (ll v : group) {
            if (v == 0) has_0 = 1;
            if (v == N-1) has_n = 1;
        }
        if (is_cycle and has_0 and has_n) {
            print("INF");
            return 0;
        }
    }

    vector<bool> visited(N);
    vector<ll> dp(N);
    auto dfs = [&](auto&& f, ll u) -> bool {
        if (visited[u]) return 0;
        if (u == N-1) return 1;
        visited[u] = 1;
        bool ok;
        for (auto [v, c] : nodes[u]) {
            if (f(f, v)) {
                ok = 1;
                dp[u] += c;
                dp[u] %= MOD;
                dp[u] += dp[v];
                dp[u] %= MOD;
            }
        }
        return ok;
    };
    dfs(dfs, 0);
    print(dp[0]);
    return 0;
}