#include<bits/stdc++.h>
using namespace std;
const long long maxn=100000+10,maxm=200000+10;
struct yal{
long long u,v,c,w;
long long getad(long long fu){
return (u^v^fu);
}
}alle[maxm];
long long n,m,vis[maxn];
long long mainres=-1;
vector<long long>adj[maxn];
map<long long,long long>sum[maxn];
map<long long,vector<long long>>all[maxn];
void vorod(){
cin>>n>>m;
for(long long i=0;i<m;i++){
cin>>alle[i].u>>alle[i].v>>alle[i].c>>alle[i].w;
adj[alle[i].u].push_back(i);
adj[alle[i].v].push_back(i);
sum[alle[i].u][alle[i].c]+=alle[i].w;
sum[alle[i].v][alle[i].c]+=alle[i].w;
all[alle[i].u][alle[i].c].push_back(i);
all[alle[i].v][alle[i].c].push_back(i);
}
}
set<pair<long long,pair<long long,long long>>>st;
void aval(long long u,long long w){
for(auto x:adj[u]){
long long v=alle[x].getad(u);
st.insert(make_pair(w+min(alle[x].w,sum[u][alle[x].c]-alle[x].w),make_pair(v,-1)));
st.insert(make_pair(w,make_pair(v,x)));
}
}
void upd(long long u,long long ind,long long w){
if(ind==-1){
return ;
}
long long f=0;
for(auto x:all[u][alle[ind].c]){
if(x==ind){
f=1;
continue;
}
long long v=alle[x].getad(u);
st.insert(make_pair(w+sum[u][alle[x].c]-alle[x].w,make_pair(v,-1)));
}
all[u][alle[ind].c].clear();
if(f){
all[u][alle[ind].c].push_back(ind);
}
}
void solve(){
aval(1,0);
vis[1]=1;
while((long long)st.size()>0){
auto x=*st.begin();
st.erase(x);
long long u=x.second.first,w=x.first,from=x.second.second;
if(x.second.first==n&&from==-1){
mainres=x.first;
return ;
}
if(vis[u]==0&&from==-1){
aval(u,w);
vis[u]=1;
}
upd(u,from,w);
}
}
void khor(){
cout<<mainres<<"\n";
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
// freopen("inp.txt","r",stdin);
vorod();
solve();
khor();
}
