#include <iostream>
#include <string.h>
#include <stdio.h>
#define min(x,y) ((x)<(y)?(x):(y))
using namespace std;struct node
{int x,y,b,c;
};struct Node
{int v,cap,flow,next;Node(){}Node(int _v,int _cap,int _flow,int _next){v=_v;cap=_cap;flow=_flow;next=_next;}
};const int INF=1000000000;
Node edges[120005];
node info[10005];
int n,m,s,t,S,T,head[1005],e;
int num[1005],h[1005],curedge[1005],pre[1005];void Add(int u,int v,int cap)
{edges[e]=Node(v,cap,0,head[u]);head[u]=e++;edges[e]=Node(u,0,0,head[v]);head[v]=e++;
}int Maxflow(int s,int t,int n)
{int ans=0,i,k,x,d,u;memset(num,0,sizeof(num));memset(h,0,sizeof(h));for(i=0;i<=n;i++) curedge[i]=head[i];num[n]=n;u=s;while(h[u]<n){if(u==t){d=INF+1;for(i=s;i!=t;i=edges[curedge[i]].v) if(d>edges[curedge[i]].cap)k=i,d=edges[curedge[i]].cap;for(i=s;i!=t;i=edges[curedge[i]].v){x=curedge[i];edges[x].cap-=d;edges[x].flow+=d;edges[x^1].cap+=d;edges[x^1].flow-=d;}ans+=d;u=k;}for(i=curedge[u];i!=-1;i=edges[i].next) if(edges[i].cap>0&&h[u]==h[edges[i].v]+1)break;if(i!=-1){curedge[u]=i;pre[edges[i].v]=u;u=edges[i].v;}else{if(--num[h[u]]==0) break;curedge[u]=head[u];for(x=n,i=head[u];i!=-1;i=edges[i].next) if(edges[i].cap>0&&h[edges[i].v]<x)x=h[edges[i].v];h[u]=x+1;num[h[u]]++;if(u!=s) u=pre[u];}}return ans;
}int in[105],out[105];int main()
{memset(head,-1,sizeof(head));e=0;int ans1,ans2,ans,i,sum=0;scanf("%d%d",&n,&m);if(n==0){puts("Impossible");return 0;}s=1;t=n;S=n+1;T=n+2;for(i=1;i<=m;i++){scanf("%d%d%d%d",&info[i].x,&info[i].y,&info[i].b,&info[i].c);if(info[i].c){sum+=info[i].b;in[info[i].y]+=info[i].b;out[info[i].x]+=info[i].b;Add(info[i].x,info[i].y,0);}else Add(info[i].x,info[i].y,info[i].b);}for(i=1;i<=n;i++){Add(S,i,in[i]);Add(i,T,out[i]);}Add(t,s,INF);if(Maxflow(S,T,n+2)!=sum){puts("Impossible");return 0;}ans1=edges[head[t]^1].cap;edges[head[t]].cap=0;edges[head[t]^1].cap=0;ans2=Maxflow(t,s,n+2);ans=ans1-ans2;if(ans<0){edges[head[t]].cap=0;edges[head[t]^1].cap=0;edges[e]=Node(s,-ans,0,head[S]);head[S]=e++;Maxflow(S,t,n+2);ans=0;}printf("%d\n",ans);for(i=1;i<=m;i++) printf(i==1?"%d":" %d",edges[i+i-1].cap+info[i].b*info[i].c);puts("");return 0;
}

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <cmath>
#include <vector>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <map>#define max(x,y) ((x)>(y)?(x):(y))
#define min(x,y) ((x)<(y)?(x):(y))
#define abs(x) ((x)>=0?(x):-(x))
#define i64 long long
#define u32 unsigned int
#define u64 unsigned long long
#define clr(x,y) memset(x,y,sizeof(x))
#define CLR(x) x.clear()
#define ph(x) push(x)
#define pb(x) push_back(x)
#define Len(x) x.length()
#define SZ(x) x.size()
#define PI acos(-1.0)
#define sqr(x) ((x)*(x))
#define MP(x,y) make_pair(x,y)
#define EPS 1e-9#define FOR0(i,x) for(i=0;i<x;i++)
#define FOR1(i,x) for(i=1;i<=x;i++)
#define FOR(i,a,b) for(i=a;i<=b;i++)
#define FORL0(i,a) for(i=a;i>=0;i--)
#define FORL1(i,a) for(i=a;i>=1;i--)
#define FORL(i,a,b)for(i=a;i>=b;i--)
using namespace std;void RD(int &x){scanf("%d",&x);}
void RD(u32 &x){scanf("%u",&x);}
void RD(double &x){scanf("%lf",&x);}
void RD(int &x,int &y){scanf("%d%d",&x,&y);}
void RD(u32 &x,u32 &y){scanf("%u%u",&x,&y);}
void RD(double &x,double &y){scanf("%lf%lf",&x,&y);}
void RD(int &x,int &y,int &z){scanf("%d%d%d",&x,&y,&z);}
void RD(int &x,int &y,int &z,int &t){scanf("%d%d%d%d",&x,&y,&z,&t);}
void RD(u32 &x,u32 &y,u32 &z){scanf("%u%u%u",&x,&y,&z);}
void RD(double &x,double &y,double &z){scanf("%lf%lf%lf",&x,&y,&z);}
void RD(char &x){x=getchar();}
void RD(char *s){scanf("%s",s);}
void RD(string &s){cin>>s;}void PR(int x) {printf("%d\n",x);}
void PR(int x,int y) {printf("%d %d\n",x,y);}
void PR(i64 x) {printf("%lld\n",x);}
void PR(u32 x) {printf("%u\n",x);}
void PR(double x) {printf("%.5lf\n",x);}
void PR(char x) {printf("%c\n",x);}
void PR(char *x) {printf("%s\n",x);}
void PR(string x) {cout<<x<<endl;}struct Node
{int u,v,cap,flow,next;
};const int INF=1000000000;
Node edges[120005];
int n,m,s,t,head[1005],e;
int num[1005],h[1005],curedge[1005],pre[1005];void add(int u,int v,double cap)
{edges[e].u=u;edges[e].v=v;edges[e].cap=cap;edges[e].flow=0.0;edges[e].next=head[u];head[u]=e++;
}void Add(int u,int v,double cap)
{add(u,v,cap);add(v,u,0.0);
}int Maxflow(int s,int t,int n)
{int ans=0,i,k,x,d,u;memset(num,0,sizeof(num));memset(h,0,sizeof(h));for(i=0;i<=n;i++) curedge[i]=head[i];num[n]=n;u=s;while(h[u]<n){if(u==t){d=INF+1;for(i=s;i!=t;i=edges[curedge[i]].v) if(d>edges[curedge[i]].cap)k=i,d=edges[curedge[i]].cap;for(i=s;i!=t;i=edges[curedge[i]].v){x=curedge[i];edges[x].cap-=d;edges[x].flow+=d;edges[x^1].cap+=d;edges[x^1].flow-=d;}ans+=d;u=k;}for(i=curedge[u];i!=-1;i=edges[i].next) if(edges[i].cap>0&&h[u]==h[edges[i].v]+1)break;if(i!=-1){curedge[u]=i;pre[edges[i].v]=u;u=edges[i].v;}else{if(--num[h[u]]==0) break;curedge[u]=head[u];for(x=n,i=head[u];i!=-1;i=edges[i].next) if(edges[i].cap>0&&h[edges[i].v]<x)x=h[edges[i].v];h[u]=x+1;num[h[u]]++;if(u!=s) u=pre[u];}}return ans;
}struct Info
{int u,v,b,c;void read(){RD(u,v,b,c);if(c==0) c=b,b=0;else c=b;}
};Info a[10005];
int in[105],out[105];int OK(int mid)
{clr(head,-1); e=0;clr(in,0),clr(out,0);int i,sum=0,x;a[m+1].u=n; a[m+1].v=1;a[m+1].b=0; a[m+1].c=mid;FOR1(i,m+1){in[a[i].v]+=a[i].b;out[a[i].u]+=a[i].b;Add(a[i].u,a[i].v,a[i].c-a[i].b);}int S=0,T=n+1;FOR1(i,n){x=in[i]-out[i];if(x>=0) Add(S,i,x),sum+=x;else Add(i,T,-x);}return Maxflow(S,T,T+1)>=sum;
}int main()
{RD(n,m);int i;FOR1(i,m) a[i].read();int low=0,high=INF,mid;while(low<=high){mid=(low+high)>>1;if(OK(mid)) high=mid-1;else low=mid+1;}int ans;if(high>=0&&OK(high)) ans=high;else if(OK(low)) ans=low;else ans=-1;if(ans==-1){puts("Impossible");return 0;}PR(ans);FOR1(i,m){if(i!=1) putchar(' ');printf("%d",edges[i+i-1].cap+a[i].b);}puts("");return 0;
}