#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define vi vector<int>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vvi vector<vi>
#define vll vector<ll>
#define vvll vector<vector<ll>>
#define vpii vector<pair<int,int>>
#define vpll vector<pair<ll,ll>>
#define vb vector<bool>
#define vs vector<string>
///............x...........///
#define all(a) a.begin(), a.end()
#define allr(a) a.rbegin(), a.rend()
#define mp(a, b) make_pair(a, b)
#define pb push_back
#define ff first
#define ss second
#define bg begin()
#define UNIQUE(X) (X).erase(unique(all(X)), (X).end())
#define ft cout << "for test"<<endl;
#define read(v, a, n) for (int i = a; i<n; i++)cin>>v[i];
#define print(v) for (auto it : v)cout << it<<' ';cout << endl;
#define PI acos(-1.0)
#define yes cout <<"Yes"<< endl
#define no cout<<"No"<<endl
#define FIO ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define t_c int test, cs = 1;cin>>test;while (test--)
#define casep cout<<"Case"<< cs++<<": ";
///................function.....................///
#define D(a) (double)(a)
#define sqr(a) (a * a)
#define siz(s) (int)(s.size())
#define max3(a, b, c) max(a, max(b, c))
#define min3(a, b, c) min(a, min(b, c))
#define Min(a) *min_element(all(a))
///#define mod 1000000007
///.........Graph.........///
int X[] = {1, -1, 0, 0};
int Y[] = {0, 0, 1, -1};
///........constant........///
const ll N = 1e6+5;
const ll inf = 1e17;
int n,m;
struct tp{
int node,color;
ll changeCost;
tp(int a, int b, int c){
node = a;
color = b;
changeCost = c;
}
};
map<pair<int,ll>,int>cnt;
vector<vector<tp>>g(N);
int main(){
FIO;
cin>>n>>m;
int a,b,c;
ll p;
for(int i=0; i<m; i++){
cin>>a>>b>>c>>p;
g[a].pb(tp(b,c,p));
g[b].pb(tp(a,c,p));
cnt[mp(a,c)]++;
cnt[mp(b,c)]++;
}
queue<int>q;
q.push(1);
vll Cost(n+1,inf),inqueue(n+1);
Cost[1]=0;
inqueue[1]=1;
while(!q.empty()){
int u = q.front();
q.pop();
for(auto to:g[u]){
int color = to.color;
int node = to.node;
ll cost = Cost[u]+((cnt[mp(u,color)]>1)? to.changeCost:0ll);
if(Cost[node]>cost){
Cost[node]=cost;
if(!inqueue[node])q.push(node);
}
}
}
cout<<(Cost[n]==inf?-1:Cost[n])<<endl;
}
