#include <bits/stdc++.h>
#include <unordered_map>
using namespace std;
typedef long long ll;
struct Line {
int to, col;
ll cost;
int cc;
};
struct Q {
int pos;
ll cost;
};
bool operator<(const Q& a, const Q& b) {
return a.cost > b.cost;
}
vector<vector<Line>> V;
vector<int> tidx;
vector<vector<int>> vidx;
vector<map<int, int>> cidx;
vector<vector<vector<Line>>> vcole;
vector<vector<int>> colcnt;
vector<vector<ll>> colsum;
vector<ll> dst;
int main() {
ios::sync_with_stdio(0);
cin.tie(0), cout.tie(0);
int n, m; cin >> n >> m;
V.resize(n + 1); cidx.resize(n + 1);
colcnt.resize(n + 1); colsum.resize(n + 1);
vcole.resize(n + 1); vidx.resize(n + 1);
tidx.resize(n + 1); cidx.resize(n + 1);
int vnum = n + 1;
for (int i = 0; i < m; i++) {
int from, to, col; ll cost; cin >> from >> to >> col >> cost;
if (cidx[from].find(col) == cidx[from].end()) {
vidx[from].push_back(vnum++);
cidx[from][col] = tidx[from]++;
vcole[from].push_back(vector<Line>());
colcnt[from].push_back(0); colsum[from].push_back(0);
}
if (cidx[to].find(col) == cidx[to].end()) {
vidx[to].push_back(vnum++);
cidx[to][col] = tidx[to]++;
vcole[to].push_back(vector<Line>());
colcnt[to].push_back(0); colsum[to].push_back(0);
}
int fromc = cidx[from][col], toc = cidx[to][col];
colcnt[from][fromc]++, colsum[from][fromc] += cost;
colcnt[to][toc]++, colsum[to][toc] += cost;
vcole[from][fromc].push_back({ to, col, cost });
vcole[to][toc].push_back({ from, col, cost });
V[from].push_back({ to, col, cost, fromc });
V[to].push_back({ from, col, cost, toc });
}
dst.resize(vnum + 1, 1e18);
for (int i = n + 1; i < vnum; i++) V.push_back(vector<Line>());
for (int i = 1; i <= n; i++) {
int sz = V[i].size();
for (int j = 0; j < sz; j++) {
Line& w = V[i][j];
int idx = cidx[w.to][w.col];
V[i].push_back({ vidx[w.to][idx], w.col, 0, idx });
}
for (auto& p : cidx[i]) {
int col = p.first, idx = p.second;
for (Line& w : vcole[i][idx])
V[vidx[i][idx]].push_back({ w.to, w.col, colsum[i][idx] - w.cost, idx });
}
}
priority_queue<Q> pq;
pq.push({ 1, 0 }); dst[1] = 0;
while (!pq.empty()) {
Q top = pq.top(); pq.pop();
if (top.pos == n) break;
for (Line& w : V[top.pos]) {
ll& ret = dst[w.to];
if (top.pos <= n) {
if (w.to > n) {
if (ret > top.cost) {
ret = top.cost;
pq.push({ w.to, ret });
}
}
else {
int idx = w.cc;
if (colcnt[top.pos][idx] == 1) {
if (ret > top.cost) {
ret = top.cost;
pq.push({ w.to, ret });
}
}
else {
if (ret > top.cost + w.cost) {
ret = top.cost + w.cost;
pq.push({ w.to, ret });
}
if (ret > top.cost + colsum[top.pos][idx] - w.cost) {
ret = top.cost + colsum[top.pos][idx] - w.cost;
pq.push({ w.to, ret });
}
}
}
}
else {
if (ret > top.cost + w.cost) {
ret = top.cost + w.cost;
pq.push({ w.to, ret });
}
}
}
}
cout << (dst[n] == 1e18 ? -1 : dst[n]) << "\n";
return 0;
}
