#include <bits/stdc++.h>

#define rep(i,n) for(int i=0;i<(n);i++)

using namespace std;
using lint=long long;

const int V_MAX=100001;
const int CAPA_INF=1<<29;
const lint COST_INF=1LL<<61;

template<class capa_t,class cost_t>
struct edge{
	int v,rev;
	capa_t capa;
	cost_t cost;
	capa_t flow;
};

template<class capa_t,class cost_t>
void add_directed_edge(vector< edge<capa_t,cost_t> > *G,int u,int v,capa_t capa,cost_t cost){
	G[u].push_back((edge<capa_t,cost_t>){v,G[v].size()  ,capa, cost,0});
	G[v].push_back((edge<capa_t,cost_t>){u,G[u].size()-1,   0,-cost,0});
}

template<class capa_t,class cost_t>
pair<capa_t,cost_t> augment(int n,vector< edge<capa_t,cost_t> > *G,int s,int t,cost_t *pot){
	static int pre[V_MAX];
	static cost_t d[V_MAX];
	rep(u,n) d[u]=(u==s?0:COST_INF);

	// Dijkstra
	bool ok=false;
	priority_queue< pair<cost_t,int> > Q; Q.push(make_pair(0,s));
	while(!Q.empty()){
		int u=Q.top().second;
		cost_t cost=-Q.top().first; Q.pop();

		if(cost<d[u]) continue;
		if(u==t) ok=true;

		rep(i,G[u].size()){
			edge<capa_t,cost_t> &e=G[u][i];
			cost_t cost2=cost+e.cost+pot[u]-pot[e.v];
			if(e.capa-e.flow>0 && cost2<d[e.v]){
				d[e.v]=cost2;
				pre[e.v]=e.rev;
				Q.push(make_pair(-cost2,e.v));
			}
		}
	}

	if(!ok) return make_pair(0,0);

	capa_t water=CAPA_INF;
	for(int v=t;v!=s;){
		edge<capa_t,cost_t> &e1=G[v][pre[v]];
		edge<capa_t,cost_t> &e2=G[e1.v][e1.rev];
		water=min(water,e2.capa-e2.flow);
		v=e1.v;
	}

	cost_t cost=0;
	for(int v=t;v!=s;){
		edge<capa_t,cost_t> &e1=G[v][pre[v]];
		edge<capa_t,cost_t> &e2=G[e1.v][e1.rev];
		e1.flow-=water;
		e2.flow+=water;
		cost+=water*e2.cost;
		v=e1.v;
	}

	rep(u,n) pot[u]+=d[u];

	return make_pair(water,cost);
}

template<class capa_t,class cost_t>
pair<capa_t,cost_t> primal_dual(int n,vector< edge<capa_t,cost_t> > *G,int s,int t){
	static cost_t pot[V_MAX];
	rep(u,n) pot[u]=0;

	capa_t ans1=0;
	cost_t ans2=0;
	while(1){
		pair<capa_t,cost_t> tmp=augment(n,G,s,t,pot);
		if(tmp.first==0) break;
		ans1+=tmp.first;
		ans2+=tmp.second;
	}
	return make_pair(ans1,ans2);
}

int main(){
	int n,m; scanf("%d%d",&n,&m);
	vector<edge<int,lint>> G[V_MAX];
	rep(i,m){
		int u,v;
		lint c1,c2; scanf("%d%d%lld%lld",&u,&v,&c1,&c2); u--; v--;
		add_directed_edge(G,u,v,1,c1);
		add_directed_edge(G,u,v,1,c2);
		add_directed_edge(G,v,u,1,c1);
		add_directed_edge(G,v,u,1,c2);
	}
	add_directed_edge(G,n-1,n,2,0LL);
	printf("%lld\n",primal_dual(n+1,G,0,n).second);

	return 0;
}