#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll Maxn=2.2e5+7,inf=4557430888798830399;
ll n,m,s,t;
namespace IO{
	template <typename T,typename... Args>inline istream& qread(T &x){return cin>>x;}
	template<typename T, typename... Args>inline ostream& write(const T& t){return cout<<t;}
	template <typename T,typename... Args>
	inline istream& qread(T &x,Args &... rest){
		cin>>x;
		return qread(rest...);
	}
	template <typename T,typename ... Args>
	inline ostream& write(const T& t1,const Args&... rest){
		cout<<t1;
		return write(rest...);
	}
}
using namespace IO;
struct edge1{
	ll u,v,w;
}ve[Maxn];
class Dinic{
	public:
		inline void modify(ll x){
			v[e[x].v].push_back(x*2+1);
		}
		inline void addEdge(ll u,ll v1,ll w){
			e.push_back(edge1{u,v1,w});
			e.push_back(edge1{v1,u,0});
			v[u].push_back(e.size()-2);
		}
		inline ll dinic(){
			ll ans=0;
			while(bfs()){
				memset(now,0,sizeof now);
				ans+=dfs(s,inf);
			}
			return ans;
		}
	private:
		vector<ll>v[Maxn];
		vector<edge1>e;
		ll dis[Maxn],now[Maxn],que[Maxn];
		inline bool bfs(void){
			memset(dis,0x3f,sizeof dis);
			ll l=1,r=1;que[1]=s;dis[s]=0;
			while(l<=r){
				ll p=que[l++],to;
				for(ll i:v[p])
					if(e[i].w&&dis[to=e[i].v]>1e9)
						dis[to]=dis[p]+1,que[++r]=to;
			}
			return dis[t]<1e9;
		}
		ll dfs(ll u,ll flow){
			if(u==t||!flow) return flow;
			ll sf=0,flw;
			for(ll &i=now[u],to;i<(ll)v[u].size();++i){
				edge1 &E=e[v[u][i]];
				if(dis[to=E.v]==dis[u]+1&&(flw=dfs(to,min(flow,E.w)))){
					E.w-=flw;e[v[u][i]^1].w+=flw;
					flow-=flw;sf+=flw;
					if(!flow)break;
				}
			}
			return sf;
		}
}fx;
ll G;
int main(int argc,char **argv){
	qread(n,m,s,t);
	for(ll i=0;i<m;i++) qread(ve[i].u,ve[i].v,ve[i].w);
	sort(ve,ve+m,[](edge1 x,edge1 y){return x.w>y.w;});
	for(ll g:{0,1})
		for(ll p=1<<30,i=0;p;p>>=1){
			while(i<m&&ve[i].w>=p){		
				if(g) fx.modify(i);
				else fx.addEdge(ve[i].u,ve[i].v,ve[i].w);
				++i;
			}
			G+=fx.dinic();
		}
	write(G);
	return 0;
}