#include <map>
#include <vector>
#include <iostream>
#include <algorithm>
#define int int64_t
using namespace std;
struct fair
{
int x, t, p, num;
};
bool faircomp(fair f1, fair f2)
{
if (f1.t != f2.t) return f1.t < f2.t;
return f1.x < f2.x;
}
struct hull
{
map<int,int> treasuremap;
int up;
int down;
int calcdist(int from, int to)
{
int dist = abs(to - from);
if (from > to) return dist*up;
return dist*down;
}
int query(int pos)
{
auto next = treasuremap.upper_bound(pos);
int res = -1e12;
if (next != treasuremap.end())
{
int x = (*next).first;
int v = (*next).second;
res = max(res, v - calcdist(x, pos));
}
if (next != treasuremap.begin())
{
auto bef = prev(next);
int x = (*bef).first;
int v = (*bef).second;
res = max(res, v - calcdist(x, pos));
}
return res;
}
void add(int pos, int val)
{
if (query(pos) > val) return;
treasuremap.insert({pos, val});
map<int,int>::iterator itn = next(treasuremap.find(pos));
map<int,int>::iterator itb = treasuremap.find(pos);
while (itn != treasuremap.end())
{
if (val - calcdist(pos, (*itn).first) >= (*itn).second)
{
itn = treasuremap.erase(itn);
}
else break;
}
while (itb != treasuremap.begin())
{
auto it = prev(itb);
if (val - calcdist(pos, (*it).first) >= (*it).second)
{
itb = treasuremap.erase(it);
}
else break;
}
}
};
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int n, d, u, s;
cin >> n >> d >> u >> s;
map<int,int> active;
vector<fair> ofairs;
for (int i = 0; i < n; i++)
{
fair nf;
nf.num = i;
cin >> nf.t >> nf.x >> nf.p;
ofairs.push_back(nf);
}
sort(ofairs.begin(), ofairs.end(), faircomp);
vector<vector<fair>> fairs;
int last = -1;
vector<fair> cf;
for (auto f : ofairs)
{
if (f.t != last)
{
if (last != -1)
{
fairs.push_back(cf);
cf.clear();
}
}
last = f.t;
cf.push_back(f);
}
fairs.push_back(cf);
/*
cout << "\n";
for (auto fl : fairs)
{
for (auto f : fl)
{
cout << f.t << " " << f.num << "\n";
}
cout << "\n";
}*/
hull h;
h.up = u;
h.down = d;
h.add(s, 0);
for (auto fl : fairs)
{
int cn = fl.size();
vector<int> cstr(cn);
vector<int> cstrl(cn);
int q = -1e12;
int lp = -1e4;
for (int i = 0; i < cn; i++)
{
cstr[i] = max(q - h.calcdist(lp, fl[i].x), h.query(fl[i].x)) + fl[i].p;
lp = fl[i].x;
q = cstr[i];
}
q = -1e12;
lp = 1e8;
for (int i = cn - 1; i >= 0; i--)
{
cstrl[i] = max(q - h.calcdist(lp, fl[i].x), h.query(fl[i].x)) + fl[i].p;
lp = fl[i].x;
q = cstrl[i];
}
for (int i = 0; i < cn; i++)
{
h.add(fl[i].x, max(cstr[i], cstrl[i]));
}
}
cout << h.query(s) << "\n";
}
