#include "bits/stdc++.h"
#include<unordered_map>
#include<unordered_set>
#pragma warning(disable:4996)
using namespace std;


typedef int  Weight;
struct Edge {
	int  dest;
	int cap, rev;
	Weight weight;
	bool operator < (const Edge &rhs) const { return weight > rhs.weight; }
};

const int V = 6010;
typedef vector<Edge> Edges;
typedef vector<Edges> Graph;
typedef vector<Weight> Array;
typedef vector<Array> Matrix;
Weight h[V];                //??????????????£???
Weight dist[V];             //???????????¢
int prevv[V], preve[V];  //??´???????????¨??????

void add_edge(Graph &g, int src, int dest, int cap, Weight weight) {
	g[src].push_back(Edge{ dest, cap, (int)g[dest].size(), weight });
	g[dest].push_back(Edge{ src, 0, (int)g[src].size() - 1, -weight });
}
#define REP(i,n) for(int i=0;i<(int)n;++i)
#define FOR(i,c) for(auto i=(c).begin();i!=(c).end();++i)
#define ALL(c) (c).begin(), (c).end()
const Weight INF = 1e9;
const Weight ZERO=0;
//????????????double?????????eps?????????
Weight min_cost_flow(Graph &g, int s, int t, int f) {
	Weight res = ZERO;
	memset(h, ZERO, sizeof(h));
	typedef pair<Weight, int> P;
	REP(i, g.size()/2-1) {
		int v=i+2;
		REP(j, g[v].size()) {
			Edge &e = g[v][j];
			if (e.cap == 0) continue;
			int u = e.dest;
			h[u] = min(h[u], h[v] + e.weight);
		}
		 v = i + g.size() / 2 + 1;
		REP(j, g[v].size()) {
			Edge &e = g[v][j];
			if (e.cap == 0) continue;
			int u = e.dest;
			h[u] = min(h[u], h[v] + e.weight);
		}
	}
	while (f > 0) {
		priority_queue<P, vector<P>, greater<P> > que;
		fill(dist, dist + V, INF);
		dist[s] = 0;
		que.push(P(ZERO, s));
		while (!que.empty()) {
			P p = que.top(); que.pop();
			const int v = p.second;
			if (dist[v] < p.first) continue;
			REP(i, g[v].size()) {
				Edge &e = g[v][i];
				if (e.cap > 0 && dist[e.dest] > dist[v] + e.weight + h[v] - h[e.dest] ) {
					dist[e.dest] = dist[v] + e.weight + h[v] - h[e.dest];
					prevv[e.dest] = v;
					preve[e.dest] = i;
					que.push(P(dist[e.dest], e.dest));
				}
			}
		}
		if (dist[t] == INF) return -1;
		REP(v, V) h[v] = h[v] + dist[v];

		int d = f;
		for (int v = t; v != s; v = prevv[v]) d = min(d, g[prevv[v]][preve[v]].cap);
		f -= d;
		res = res + d * h[t];
		for (int v = t; v != s; v = prevv[v]) {
			Edge &e = g[prevv[v]][preve[v]];
			e.cap -= d;
			g[v][e.rev].cap += d;
		}
	}
	return res;
}
int main()
{
	int N;int V,Xl,Xr;cin>>N>>V>>Xl>>Xr;
	struct mogu {
		int x;
		long long int t;
		long long int p;
	};
	vector<mogu>mogus;
	mogus.push_back(mogu{ Xl,0,0 });
	mogus.push_back(mogu{ Xr,0,0 });
	for (int i = 0; i < N; ++i) {
		int x,t,p;cin>>x>>t>>p;
		mogus.push_back(mogu{ x,t,p });

	}
	sort(mogus.begin(), mogus.end(), [](const mogu&l, const mogu&r) {
		return l.t<r.t;
	});

	const int start=0;
	const int mo_in=start+1;
	const int mo_out=mo_in+N+2;
	const int goal=mo_out+N+2;
	Graph g(goal+1);
	add_edge(g,start,mo_in+1,1,0);
	add_edge(g,start,mo_in+0,1,0);
	for (int i = 0; i < N+2; ++i) {
		add_edge(g,mo_in+i,mo_out+i,1,0);
		for (int j = i+1; j < N+2; ++j) {
			const auto amogu(mogus[i]);
			const auto bmogu(mogus[j]);
			{
				long long int time=bmogu.t-amogu.t;
				if (time*V >= abs(bmogu.x - amogu.x)) {
					add_edge(g,mo_out+i,mo_in+j,1,-bmogu.p);
				}
			}
		}
		add_edge(g,mo_out+i,goal,1,0);
	}
	Weight ans=min_cost_flow(g,start,goal,2);
	cout<<-ans<<endl;
	return 0;
}

Measured memory_bytes: 242232