#include <iostream>
#include <stdio.h>
#include <cstring>
#include <vector>
#include <queue>
#define INF 0x3f3f3f3f
using namespace std;
const int maxn = 600;
struct Edge
{int from,to,cap,flow,cost;Edge() {}Edge(int a,int b,int c,int d,int e):from(a),to(b),cap(c),flow(d),cost(e) {}
};
struct MCMF
{int n,m,s,t;vector<Edge> edges;vector<int> g[maxn];int inq[maxn];int d[maxn];int p[maxn];int a[maxn];void init(int n){this->n =n;for(int i=0; i<n; i++)g[i].clear();edges.clear();}void addedge(int from,int to,int cap,int cost){Edge e1= Edge(from,to,cap,0,cost), e2= Edge(to,from,0,0,-cost);edges.push_back(e1);edges.push_back(e2);m=edges.size();g[from].push_back(m-2);g[to].push_back(m-1);}bool spfa(int s,int t, int & flow,int & cost){for(int i=0; i<n; i++)d[i]=INF;memset(inq,0,sizeof(inq));d[s]=0;inq[s]=1;p[s]=0;a[s]=INF;queue<int>q;q.push(s);while(!q.empty()){int u=q.front();q.pop();inq[u]=0;for(int i=0; i<g[u].size(); i++){Edge & e = edges[g[u][i]];if(e.cap>e.flow && d[e.to]>d[u]+e.cost){d[e.to]=d[u]+e.cost;p[e.to]=g[u][i];a[e.to]=min(a[u],e.cap-e.flow);if(!inq[e.to]){q.push(e.to);inq[e.to]=1;}}}}if(d[t]==INF)return false;flow+=a[t];cost+=a[t]*d[t];for(int u=t; u!=s; u=edges[p[u]].from){edges[p[u]].flow +=a[t];edges[p[u]^1].flow-=a[t];}return true;}int  MincostMaxflow(int s,int t){int flow=0,cost =0;while(spfa(s,t,flow,cost));return cost;}
} sol;int main()
{freopen("input.txt","r",stdin);freopen("output.txt","w",stdout);int n,m,cas=1;while(scanf("%d%d",&n,&m)!=EOF){int s=0,t=n+1;sol.init(n+2);while(m--){int u,v,c,ad;scanf("%d%d%d%d",&u,&v,&c,&ad);sol.addedge(u,v,1,c);sol.addedge(u,v,1,c+ad);}sol.addedge(s,1,2,0);sol.addedge(n,t,2,0);printf("Case %d: %d\n",cas++,sol.MincostMaxflow(s,t));}
}