#include <bits/stdc++.h>
#define int long long
using namespace std;
struct Arc {
int nex, pds, col;
};
struct Sit {
int i, col, t;
bool operator <(const Sit& other) const {
return t > other.t;
}
};
const int N = 1e5 + 42, M = 4e5 + 42, INF = 1e18 + 42;
int n, m, id = 0;
priority_queue<Sit> q;
vector<Arc> adj[N], adjCol[M];
unordered_map<int, int> idAdj[N];
unordered_map<int, int> tot[N], dist[N];
void Dijkstra() {
while(!q.empty()) {
Sit sit = q.top();
q.pop();
int i = sit.i, col = sit.col, t = sit.t;
if(t == dist[i][col]) {
if(col == 0) {
for(Arc arc : adj[i]) {
if(tot[i][arc.col] == arc.pds) {
if(dist[arc.nex][0] > t) {
dist[arc.nex][0] = t;
q.push({arc.nex, 0, t});
}
} else if(dist[arc.nex][0] > t + arc.pds) {
dist[arc.nex][0] = t + arc.pds;
q.push({arc.nex, 0, t + arc.pds});
}
if(dist[arc.nex][arc.col] > t) {
dist[arc.nex][arc.col] = t;
q.push({arc.nex, arc.col, t});
}
}
} else {
t += tot[i][col];
int j = idAdj[i][col];
for(Arc arc : adjCol[j])
if(dist[arc.nex][0] > t - arc.pds) {
dist[arc.nex][0] = t - arc.pds;
q.push({arc.nex, 0, t - arc.pds});
}
}
}
}
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> n >> m;
for(int i = 0; i < m; i++) {
int a, b, col, pds;
cin >> a >> b >> col >> pds;
a--, b--;
tot[a][col] += pds;
tot[b][col] += pds;
adj[a].push_back({b, pds, col});
adj[b].push_back({a, pds, col});
dist[a][col] = dist[b][col] = INF;
if(idAdj[a].find(col) == idAdj[a].end())
idAdj[a][col] = id++;
if(idAdj[b].find(col) == idAdj[b].end())
idAdj[b][col] = id++;
adjCol[idAdj[a][col]].push_back({b, pds, col});
adjCol[idAdj[b][col]].push_back({a, pds, col});
}
for(int i = 0; i < n; i++)
dist[i][0] = INF;
for(auto p : dist[0]) {
q.push({0, p.first, 0});
dist[0][p.first] = 0;
}
Dijkstra();
if(dist[n-1][0] == INF)
cout << -1;
else
cout << dist[n-1][0];
}
