#include<bits/stdc++.h>
#define INF INT_MAX
using namespace std;
const int N=5e4+10,M=2.5e5+10;
int n,m,st,ed,S,T;
struct edge{
	int x,y,c,pre;
}a[M*2];
int alen,last[N],cur[N];
void ins(int x,int y,int c)
{
	a[++alen]={x,y,c,last[x]};
	last[x]=alen;
}
int f[N],h[N];
bool bfs()
{
	memset(h,0,sizeof(h));h[S]=1;
	deque<int> q;q.push_back(S);
	while(!q.empty())
	{
		int x=q.front();q.pop_front();
		for(int k=last[x];k;k=a[k].pre)
		{
			int y=a[k].y;
			if(!h[y]&&a[k].c)
			{
				h[y]=h[x]+1;
				q.push_back(y);
			}
		}
	}
	return h[T];
}
int Dinic(int x,int f)
{
	if(x==T) return f;
	int sx=0;
	for(int k=cur[x];k;k=a[k].pre)
	{
		cur[x]=k;
		int y=a[k].y;
		if(h[y]==h[x]+1&&a[k].c&&sx<f)
		{
			int sy=Dinic(y,min(a[k].c,f-sx));
			a[k].c-=sy,a[k^1].c+=sy;
			sx+=sy;
			if(sx==f) break;
		}
	}
	if(sx==0) h[x]=0;
	return sx;
}
int main()
{
	scanf("%d%d%d%d",&n,&m,&st,&ed);
	S=n+1,T=n+2;
	alen=1;memset(last,0,sizeof(last));
	for(int i=1;i<=m;i++)
	{
		int x,y,u,v;
		scanf("%d%d%d%d",&x,&y,&u,&v);
		ins(x,y,v-u),ins(y,x,0);
		f[x]-=u,f[y]+=u;
	}
	int sum1=0,sum2=0;
	for(int i=1;i<=n;i++)
	{
		if(f[i]>0) ins(S,i,f[i]),ins(i,S,0),sum1+=f[i];
		if(f[i]<0) ins(i,T,-f[i]),ins(T,i,0);
	}
	ins(ed,st,INF),ins(st,ed,0);
	while(bfs())
	{
		memcpy(cur,last,sizeof(last));
		sum2+=Dinic(S,INF);
	}
	if(sum1^sum2) puts("please go home to sleep");
	else
	{
		for(int k=last[S];k;k=a[k].pre) a[k].c=a[k^1].c=0;
		for(int k=last[T];k;k=a[k].pre) a[k].c=a[k^1].c=0;
		sum2=a[alen].c;
		a[alen].c=a[alen-1].c=0;
		S=ed,T=st;int sum3=0;
		while(bfs())
		{
			memcpy(cur,last,sizeof(last));
			sum3+=Dinic(S,INF);
		}
		printf("%d\n",sum2-sum3);
	}
	return 0;
}