#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; i++)
#define FORD(i, b, a) for (int i = (b), _a = (a); i >= _a; i--)
#define pa pair<ll, ll>
#define fi first
#define se second
#define bit(mask, j) ((mask >> j) & 1)
#define t_test int t;cin >> t;while(t--)
const ll mod = 1e9 + 7;
const ll INF = 1e18;
inline void adm(ll &x){if(x>=mod)x%=mod;else if(x<0)x+=mod;}
//--------------------------------------------------------------------
const ll N = 1e5 + 10;
ll n, m;
unordered_map<ll, vector<pa>> g[N];
ll d[N];
unordered_map<ll, ll> d2[N], clr[N];
void DJK() {
priority_queue<pair<ll, pa>> q;
memset(d, 0x3f, sizeof d);
d[1] = 0;
q.push({0, {1, 0}});
while(!q.empty()) {
ll u = q.top().se.fi, cost = -q.top().fi, c = q.top().se.se;
q.pop();
if(c != 0) {
if(d2[u][c] != cost) continue;
for(auto e : g[u][c]) {
ll v = e.fi, _c = c, p = e.se;
ll val = cost + clr[u][_c] - p;
if(d[v] > val) {
d[v] = val;
q.push({-d[v],{v, 0}});
}
}
}
else {
if(cost != d[u]) continue;
if(u == n) {
cout << cost;
exit(0);
}
for(auto cs : g[u]) {
ll _c = cs.fi;
for(auto e : cs.se) {
ll v = e.fi, p = e.se;
ll val = cost + clr[u][_c] - p;
if(d[v] > val) {
d[v] = val;
q.push({-d[v], {v, 0}});
}
val = cost + p;
if(d[v] > val) {
d[v] = val;
q.push({-d[v], {v, 0}});
}
val = cost;
if(!d2[v].count(_c) || d2[v][_c] > val) {
d2[v][_c] = val;
q.push({-d2[v][_c], {v, _c}});
}
}
}
}
}
}
void hbmt() {
cin >> n >> m;
FOR(i, 1, m) {
ll u, v, c, p;
cin >> u >> v >> c >> p;
g[u][c].push_back({v, p});
g[v][c].push_back({u, p});
clr[u][c] += p;
clr[v][c] += p;
}
DJK();
cout << -1;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
if(fopen("hbmt.inp", "r")) {
freopen("hbmt.inp", "r", stdin);
freopen("hbmt.out", "w", stdout);
}
// t_test
hbmt();
return 0;
}
