#include <bits/stdc++.h>
using namespace std;
struct Edge
{
size_t v, c, p;
};
constexpr size_t N = 100000;
vector<Edge> g[N];
map<size_t, size_t> ccost[N], f[N];
size_t d[N];
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
size_t n, m;
cin >> n >> m;
for (size_t i = 0; i < m; i++)
{
size_t u, v, c, p;
cin >> u >> v >> c >> p;
g[u - 1].push_back({v - 1, c, p});
g[v - 1].push_back({u - 1, c, p});
ccost[u - 1][c] += p;
ccost[v - 1][c] += p;
}
auto compare_state = [](tuple<size_t, size_t, size_t> const &a,
tuple<size_t, size_t, size_t> const &b)
{ return get<1>(a) > get<1>(b); };
priority_queue<tuple<size_t, size_t, size_t>,
vector<tuple<size_t, size_t, size_t>>, decltype(compare_state)>
q(compare_state);
fill(d + 1, d + n, SIZE_MAX);
q.emplace(0, 0, 0);
while (!q.empty())
{
auto const [u, dis, c] = q.top();
q.pop();
if ((!c && dis != d[u]) || (c && dis != f[u][c]))
continue;
for (auto const &e : g[u])
if (c) // Color just changed.
{
if (c == e.c && dis + ccost[u][e.c] - e.p < d[e.v])
{
d[e.v] = dis + ccost[u][e.c] - e.p;
q.emplace(e.v, d[e.v], 0);
}
}
else // Already paid for the change (if there was one).
{
if (f[e.v].find(e.c) == f[e.v].end() || dis < f[e.v][e.c])
{
f[e.v][e.c] = dis;
q.emplace(e.v, dis, e.c);
}
if (dis + e.p < d[e.v])
{
d[e.v] = dis + e.p;
q.emplace(e.v, d[e.v], 0);
}
if (dis + ccost[u][e.c] - e.p < d[e.v])
{
d[e.v] = dis + ccost[u][e.c] - e.p;
q.emplace(e.v, d[e.v], 0);
}
}
}
cout << (d[n - 1] == SIZE_MAX ? -1 : (int64_t)d[n - 1]) << '\n';
}
