//Autor: Bartłomiej Czarkowski
#include <bits/stdc++.h>
using namespace std;
#ifdef DEBUG
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif
const int N = 101000;
int n, m, a, b, c, p;
map<int, vector<pair<int, int>>> mp[N];
long long odl[N];
priority_queue<pair<long long, int>> pq;
int main() {
scanf("%d%d", &n, &m);
for (int i = 1; i <= m; ++i) {
scanf("%d%d%d%d", &a, &b, &c, &p);
mp[a][c].push_back({b, p});
mp[b][c].push_back({a, p});
}
for (int i = 2; i <= n; ++i) {
odl[i] = 1e18;
}
pq.push({0, 1});
while (!pq.empty()) {
long long w = -pq.top().first;
int x = pq.top().second;
pq.pop();
//~ debug(w, x);
if (x == n) {
printf("%lld\n", odl[x]);
return 0;
}
if (odl[x] != w) {
continue;
}
for (auto i : mp[x]) {
long long sum = 0;
for (auto j : i.second) {
sum += j.second;
}
for (auto [a, b] : i.second) {
if (odl[a] > w + min(sum - b, (long long)b)) {
odl[a] = w + min(sum - b, (long long)b);
pq.push({-odl[a], a});
}
}
}
}
printf("-1\n");
return 0;
}
