#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll=long long;
using Graph=vector<vector<pair<int,int>>>;
#define MAX 200003
#define MOD 1000000007
#define INF 1000000000000000000

int main(){
  int N,M;
  cin>>N>>M;
  vector<int> u(M),v(M);
  vector<ll> c(M),d(M);
  for(int i=0;i<M;i++){
    cin>>u[i]>>v[i]>>c[i]>>d[i];
    u[i]--;
    v[i]--;
  }

  mcf_graph<int,ll> G(N+2);
  for(int i=0;i<M;i++){
    G.add_edge(u[i],v[i],1,c[i]);
    G.add_edge(u[i],v[i],1,d[i]);
    G.add_edge(v[i],u[i],1,c[i]);
    G.add_edge(v[i],u[i],1,d[i]);
  }

  G.add_edge(N,0,2,0);
  G.add_edge(N-1,N+1,2,0);
  pair<int,ll> p=G.flow(N,N+1);
  cout<<p.second<<endl;
}