#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#define vi vector<int>
#define ve vector
#define ll long long
#define vl vector<ll>
#define vll vector<pair<ll,ll>>
#define onbit __builtin_popcount
#define ii pair<int,int>
#define vvi vector<vi>
#define vii vector<ii>
#define gii greater<ii>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define INF 1e18
#define eps 1e-7
#define eps1 1e-2
#define optimise ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define MAX_A 1e5+5
using namespace std;
using namespace __gnu_pbds;
template <class T>
using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int MOD = 1e9+7;
const int nax = 1e5+5;
const int MAX_VAL = 1e9;
double PI=3.14159265359;
int arx[8]={1,1,0,-1,-1,-1, 0, 1};
int ary[8]={0,1,1, 1, 0,-1,-1,-1};
typedef complex<int> Point;
#define X real()
#define Y imag()
void setIO(string s) {
freopen((s + ".in").c_str(), "r", stdin);
freopen((s + ".out").c_str(), "w", stdout);
}
int main(){
optimise;
/*#ifndef ONLINE_JUDGE
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif*/
//setIO("pump");
int n,m;
cin>>n>>m;
vector<pair<int,ll>> adj[n];
vector<pair<ll,ll>> tab(m);
vector<map<ll,ll>> check(n);
for (int i = 0; i < m; ++i)
{
int x,y,z,p;
cin>>x>>y>>z>>p;
x--;y--;
//cout <<p<<endl;
tab[i]={z,p};
check[x][z]+=p;
check[y][z]+=p;
adj[x].pb({y,i});
adj[y].pb({x,i});
}
priority_queue<pair<pair<ll,int>,pair<int,int>>,vector<pair<pair<ll,int>,pair<int,int>>>,greater<>> pq;
pq.push({{0,0},{-1,-1}});
vl dis(n,1e18);
dis[0]=0;
while(!pq.empty())
{
//return 0;
ll x=pq.top().fi.fi;
int y=pq.top().fi.se;
int z=pq.top().se.fi;
int k=pq.top().se.se;
pq.pop();
for(auto u:adj[y])
{
auto c=tab[u.se];
int node=u.fi;
ll q=check[y][c.fi];
if (c.fi==z) q-=k;
if (q<c.se){
continue;
}
if (q==c.se){
if (dis[node]<=x) continue;
pq.push({{x,node},{c}});
dis[node]=x;
}else{
ll cur=max(min(q-c.se,c.se),1ll*0);
//cout << cur<<endl;
if (dis[node]<=x+cur) continue;
pq.push({{cur+x,node},{c}});
dis[node]=cur+x;
//cout <<check[node][c.fi]<<endl;
}//return 0;
}
}
if (dis[n-1]>=1e18) cout << -1<<endl;
else
cout <<dis[n-1]<<endl;
}
