#include <bits/stdc++.h>
#define MAX 505000
using ll = long long;
ll inf = (1e9);
struct Seg3 {
ll tab[MAX*4];
void update(int t,ll k,int la=0,int ra=MAX-1,int pos=1){
if(la>t||ra<t)return;
if(la==ra){
tab[pos]=std::max(tab[pos],k);
return;
}
int m = (la+ra)/2;
update(t,k,la,m,pos*2);
update(t,k,m+1,ra,(pos*2)+1);
tab[pos]=std::max(tab[pos*2],tab[(pos*2)+1]);
}
ll query(int l,int r,int la=0,int ra=MAX-1,int pos=1){
if(la>r||ra<l)return -inf;
if(la>=l&&ra<=r){
return tab[pos];
}
int m = (la+ra)/2;
return std::max(query(l,r,la,m,pos*2),query(l,r,m+1,ra,(pos*2)+1));
}
void iniciar(void){
for(auto&x:tab)x=-inf;
}
};
ll U,D;
ll Q,S;
Seg3 upper,down;
typedef std::pair<ll,ll> pll;
typedef std::pair<ll,pll> plp;
int main()
{
std::ios::sync_with_stdio(false);
std::cin.tie(0);
std::cout.tie(0);
upper.iniciar();
down.iniciar();
std::cin>>Q>>D>>U>>S;
upper.update(S,+(U*S));
down.update(S,-(D*S));
std::vector<plp> eventos;
eventos.push_back(plp(1e9,pll(S,0)));
for(int i=0;i!=Q;++i){
ll D,L,X;
std::cin>>D>>L>>X;
eventos.push_back({D,{L,X}});
}
std::sort(eventos.begin(),eventos.end());
ll last=0;
for(auto&x:eventos){
ll local = x.second.first;
ll bonus = x.second.second;
ll descer = down.query(local,MAX-1);
ll subir = upper.query(0,local-1);
ll ans = std::max(descer+bonus+(D*local),subir+bonus-(U*local));
last=ans;
/// std::cout<<"Valor desce: "<<descer-bonus+(D*local)<<"\n";
/// std::cout<<"D: "<<descer<<" "<<"S: "<<subir<<"\n";
/// std::cout<<"Dia "<<x.first<<" Lucro: "<<ans<<" "<<local<<"\n";
down.update(local,ans-(D*local));
upper.update(local,ans+(U*local));
}
std::cout<<last<<"\n";
}
