#include <bits/stdc++.h>
using namespace std;
template<class T, class U>
void ckmin(T &a, U b)
{
if (a > b) a = b;
}
template<class T, class U>
void ckmax(T &a, U b)
{
if (a < b) a = b;
}
#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define SZ(x) ((int) (x).size())
#define ALL(x) (x).begin(), (x).end()
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
const long long LLINF = 3e18;
const int MAXN = 100013;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
int N, M;
map<int, vpi> edge[MAXN];
//you can only save it if its color is unique or its color is twice and you just used one of them & paid.
ll dist[MAXN];
map<int, int> special[MAXN];
priority_queue<array<ll, 3>, vector<array<ll, 3> >, greater<array<ll, 3> > > pq;
ll ans;
//distance, vertex, color
vpi conv(vpi v)
{
ll sum = 0;
for (pii p : v)
{
sum += p.se;
}
for (pii &p : v)
{
ckmin(p.se, sum - p.se);
}
return v;
}
int32_t main()
{
cout << fixed << setprecision(12);
cerr << fixed << setprecision(4);
ios_base::sync_with_stdio(false); cin.tie(0);
cin >> N >> M;
FOR(i, 0, M)
{
int u, v, c, d;
cin >> u >> v >> c >> d; u--; v--;
edge[u][c].PB({v, d});
edge[v][c].PB({u, d});
// edge[u].PB({v, c, d});
// edge[v].PB({u, c, d});
}
FOR(u, 0, N)
{
for (auto &p : edge[u])
{
p.se = conv(p.se);
}
}
// FOR(u, 0, N)
// {
// for (auto p : edge[u])
// {
// for (auto e : p.se)
// {
// cerr << "EDGE " << u << ' ' << e.fi << ' ' << " color " << p.fi << " dis " << e.se << endl;
// }
// }
// }
fill(dist, dist + N, LLINF);
dist[0] = 0;
pq.push({0, 0, 0});
while(!pq.empty())
{
ll d = pq.top()[0]; int u = pq.top()[1], c = pq.top()[2];
pq.pop();
if (c != 0)
{
if (d != special[u][c]) continue;
if (SZ(edge[u][c]) == 2)
{
for (auto p : edge[u][c])
{
int v = p.fi;
if (dist[v] > d)
{
dist[v] = d;
pq.push({d, v, 0});
}
}
}
}
else
{
if (d != dist[u]) continue;
for (auto p : edge[u])
{
int cl = p.fi;
for (auto e : p.se)
{
int v = e.fi, dis = e.se;
//no guarantees -> you pay iff this color is unique.
//first set the general distance
ll nd = d + dis;
// ll nd = d + dis;
if (dist[v] > nd)
{
dist[v] = nd;
pq.push({nd, v, 0});
}
//but also set the special distance
nd = d + dis;
if (special[v].find(cl) == special[v].end() || special[v][cl] > nd)
{
special[v][cl] = nd;
pq.push({nd, v, cl});
}
}
}
}
}
ans = dist[N - 1];
if (ans >= LLINF) ans = -1;
cout << ans << '\n';
return 0;
}
