#include <bits/stdc++.h>
using namespace std;

struct C {
	int b,c;
	long long v;
};

int n,m,k,s,t;
vector<C> css[200010];

bool byb(C const&c1,C const&c2){
	return c1.b<c2.b;
}
bool byc(C const&c1,C const&c2){
	return c1.c<c2.c;
}

main(){
	cin>>n>>m>>k>>s>>t;
	for(int i=0;i<m;++i){
		int a;
		C c;
		cin>>a>>c.b>>c.c;
		css[a].push_back(c);
	}
	{
		C c;
		c.c=s;
		c.v=0;
		css[0].push_back(c);
	}
	{
		C c;
		c.b=t;
		css[n].push_back(c);
	}
	for(int i=0;i<n;++i){
		if(css[i+1].empty()){
			cout<<-1;
			exit(0);
		}
		sort(css[i].begin(),css[i].end(),byc);
		int cc=css[i].size();
		for(int j=1;j<cc;++j){
			C&c0=css[i][j-1];
			C&c1=css[i][j];
			if(c1.v>c0.v+(c1.c-c0.c)){
				c1.v=c0.v+(c1.c-c0.c);
			}
		}
		for(int j=cc-2;j>=0;--j){
			C&c1=css[i][j];
			C&c0=css[i][j+1];
			if(c1.v>c0.v+(c0.c-c1.c)){
				c1.v=c0.v+(c0.c-c1.c);
			}
		}
		sort(css[i+1].begin(),css[i+1].end(),byb);
		int l=0;
		for(auto& d:css[i+1]){
			while(l<cc&&css[i][l].c<d.b){
				++l;
			}
			long long v1= l==0  ? 1<<30 : css[i][l-1].v+(d.b-css[i][l-1].c);
			long long v2= l==cc ? 1<<30 : css[i][l].v+(css[i][l].c-d.b);
			d.v=min(v1,v2);
		}
	}
	cout<<css[n][0].v;
}