#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={-1,0,1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

struct edge{
    ll to,len,num;
};

struct SCC{//多重辺、自己辺ok
    int n,k=0;
    vector<vector<int>> g,rg;
    vector<vector<long long>> ret;
    vector<int> vs,cmp;
    vector<bool> used;
    SCC(int _n){
        n=_n;
        g=vector<vector<int>>(n);rg=g;
        cmp=vector<int>(n);used=vector<bool>(n);
    }
    void add_edge(int f, int t){
        g[f].push_back(t);rg[t].push_back(f);
    }
    int init(){
        rep(i,n)if(!used[i])dfs(i);
        used=vector<bool>(n,false);
        per(i,n){
            if(!used[vs[i]]){
                rdfs(vs[i],k);
                k++;
            }
        }
        return k;
    }
    vector<vector<ll>> build(){//自己辺はないが多重辺あり
        ret.resize(k);
        rep(i,n){
            for(auto to:g[i]){
                if(cmp[i]==cmp[to])continue;
                ret[cmp[i]].push_back(cmp[to]);
            }
        }
        return ret;
    }
    private:
    void dfs(int v){
        used[v]=true;
        rep(i,g[v].size()){
            if(!used[g[v][i]])dfs(g[v][i]);
        }
        vs.push_back(v);
    }
    void rdfs(int v, int k){
        used[v]=true;cmp[v]=k;
        rep(i,rg[v].size()){
            if(!used[rg[v][i]]){
                rdfs(rg[v][i],k);
            }
        }
    }
};

const int mod = 1000000007;
const int max_n = 200005;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x=0):x((x%mod+mod)%mod){}
  mint operator-() const { return mint(-x);}
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod-a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;}
  mint operator+(const mint a) const { return mint(*this) += a;}
  mint operator-(const mint a) const { return mint(*this) -= a;}
  mint operator*(const mint a) const { return mint(*this) *= a;}
  mint pow(ll t) const {
    if (!t) return 1;
    mint a = pow(t>>1);
    a *= a;
    if (t&1) a *= *this;
    return a;
  }
  bool operator==(const mint &p) const { return x == p.x; }
  bool operator!=(const mint &p) const { return x != p.x; }
  // for prime mod
  mint inv() const { return pow(mod-2);}
  mint& operator/=(const mint a) { return *this *= a.inv();}
  mint operator/(const mint a) const { return mint(*this) /= a;}
};
istream& operator>>(istream& is, mint& a) { return is >> a.x;}
ostream& operator<<(ostream& os, const mint& a) { return os << a.x;}

int main(){
    ll n,m;cin >> n >>m;
    vector<vector<edge>> g(n+1);
    SCC t(n+1);
    rep(i,m){
        ll a,b,c,d;cin >> a >> b >> c >> d;
        g[a].pb({b,c,d});
        t.add_edge(a,b);
    }
    ll k=t.init();
    vvl ord(k);
    rep(i,n+1){
        ord[t.cmp[i]].pb(i);
    }
    bool ok=true;
    rep(i,k){
        if(ord[i].size()!=1)ok=false;
        if(ord[i][0]==n)break;
    }
    if(!ok){
        cout << "INF" <<endl;return 0;
    }
    vector<pair<mint,mint>> dp(n+1);
    dp[0]={0,1};
    rep(i,n+1){
        ll now=ord[i][0];
        if(now==n)break;
        for(auto p:g[now]){
            dp[p.to].fi+=(dp[now].fi+dp[now].se*p.len)*p.num;
            dp[p.to].se+=dp[now].se*p.num;
        }
    }
    cout << dp[n].fi <<endl;
}