#include <cstdio>
#include <stdio.h>
#include <stdbool.h>
#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
#include <cassert>
using namespace std;
#define int long long
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
int n;
vector<vector<pii> > graph;
int dijk(int s, int e){
vector<int> dj(n+1, LLONG_MAX/4);
priority_queue<pii, vector<pii>, greater<pii> > pq;
pq.push(mp(0, s));
while (pq.size()){
int d=pq.top().fi, node=pq.top().se;
pq.pop();
if (d>=dj[node])continue;
dj[node]=d;
for (auto num:graph[node])pq.push(mp(d+num.se, num.fi));
}
return dj[e];
}
int32_t main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int m, ans=LLONG_MAX/4;
cin>>n>>m;
graph.resize(n+1);
vector<pair<pii, pii> > edges(m);
vector<vector<int> > dist(n+1, vector<int>(n+1, LLONG_MAX/2));
for (int i=1; i<=n; ++i)dist[i][i]=0;
for (int i=0, a, b, c, d; i<m; ++i){
cin>>a>>b>>c>>d;
edges[i]=mp(mp(a, b), mp(c, d));
graph[a].pb(mp(b, c));
dist[a][b]=min(dist[a][b], c);
}
for (int i=1; i<=n; ++i)for (int j=1; j<=n; ++j)for (int p=1; p<=n; ++p)dist[j][p]=min(dist[j][p], dist[j][i]+dist[i][p]);
ans=min(ans, dijk(1, n)+dijk(n, 1));
for (auto c:edges)if (c.se.se+min(dist[1][n], dist[1][c.fi.se]+dist[c.fi.fi][n]+c.se.fi)+min(dist[n][1], dist[n][c.fi.se]+dist[c.fi.fi][1]+c.se.fi)<ans){
graph[c.fi.fi].erase(remove(graph[c.fi.fi].begin(), graph[c.fi.fi].end(), mp(c.fi.se, c.se.fi)));
graph[c.fi.se].pb(mp(c.fi.fi, c.se.fi));
ans=min(ans, dijk(1, n)+dijk(n, 1)+c.se.se);
graph[c.fi.se].erase(remove(graph[c.fi.se].begin(), graph[c.fi.se].end(), mp(c.fi.fi, c.se.fi)));
graph[c.fi.fi].pb(mp(c.fi.se, c.se.fi));
}
cout<<(ans==LLONG_MAX/4?-1:ans);
}
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