//
// IOI2009Salesman.cpp
//
//
// Created by Matjaz Leonardis on 11/11/2023.
//
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
vector<int> L;
vector<int> T;
vector<int> M;
int N,D,U,S;
long long distance(int L1, int L2){
if (L1 > L2) return D * (L1 - L2);
return U * (L2 - L1);
}
int main(){
cin >> N >> D >> U >> S;
vector<pair<int, pair<int,int> > > tmp(N+2);
for (int i=0;i<N;i++){
cin >> tmp[i].first >> tmp[i].second.first >> tmp[i].second.second;
}
tmp[N] = make_pair(-1, make_pair(S, 0));
tmp[N+1] = make_pair(500001, make_pair(S, 0));
sort(tmp.begin(), tmp.end());
L.assign(N+2, 0);
M.assign(N+2, 0);
for (int i=0;i<N+2;i++){
L[i] = tmp[i].second.first;
M[i] = tmp[i].second.second;
}
vector<long long> best(N+2, 0);
for (int i=N+1;i>=0;i--){
long long best_remaining;
if (i == N + 1) best_remaining = 0; else best_remaining = -distance(L[i], S);
for (int j=i+1;j<N+1;j++){
best_remaining = max(best_remaining, -distance(L[i],L[j]) + best[j]);
}
best[i] = M[i] + best_remaining;
}
cout << best[0] << endl;
return 0;
}
