#include <bits/stdc++.h>
//code
#define fl(i,x,y,z) for(int i=x;i<=y;i=i+z)
#define fn(i,x,y,z) for(int i=x;i>=y;i=i-z)
#define rep(i,x,y) for(int i=x;i<y;i=i+1)
#define all(v) v.begin(),v.end()
#define pb push_back
#define tle cout<<"tle"<<endl
#define edl cout<<"\n"
#define el "\n"
#define getbit(x,i) ((x>>i)&1)
#define bitcnt __builtin_popcount
//ham
#define pii pair<long long,long long>
#define fi first
#define se second
#define ll long long
#define ld long double
#define inf 0x3f3f3f3f
#define int long long
using namespace std;
const ll mod=1e9+7;
int n,m;
struct kb
{
int v,c,p;
};
vector <pair<int,pii>> e[100005];
vector <pii> a[100005];
int vis[1000005],t[1000005];
ll d[1000005];
priority_queue <pii,vector <pii>, greater <pii>> q;
void inp()
{
cin>>n>>m;
fl(i,1,m,1)
{
int u,v,c,p;
cin>>u>>v>>c>>p;
e[u].pb({v,{c,p}});
e[v].pb({u,{c,p}});
a[u].pb({v,p});
a[v].pb({u,p});
}
}
void dij()
{
fl(i,1,n,1) d[i]=1e18;
d[1]=0;
q.push({d[1],1});
while (!q.empty())
{
int u=q.top().se;
int c=q.top().fi;
q.pop();
if (c<d[u]) continue;
for (auto it: a[u])
{
int v=it.fi,w=it.se;
if (d[v]>d[u]+w)
{
d[v]=d[u]+w;
q.push({d[v],v});
}
}
}
if (d[n]==1e18) cout<<-1;
else cout<< d[n];
}
void sol()
{
int cur = n;
fl(i,1,n,1)
{
sort(e[i].begin(), e[i].end());
for (auto it : e[i])
t[it.fi] += it.se.se;
for (auto it : e[i])
{
if (!vis[it.fi])
{
++cur;
a[i].push_back({cur,0});
}
vis[it.fi]=1;
a[cur].push_back({it.se.fi, t[it.fi]-it.se.se});
a[it.se.fi].push_back({cur, 0});
}
for (auto it : e[i])
{
t[it.fi] = 0;
vis[it.fi] = 0;
}
}
dij();
}
signed main()
{
// freopen("task.inp","r",stdin);
// freopen("task.out","w",stdout);
ios_base::sync_with_stdio(false);
cin.tie(NULL);
inp();
sol();
return 0;
}
/* /\_/\
( ._. )
/ >V< \
*/
