#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
#define pb push_back
#define f first
#define s second
namespace debug {
const int DEBUG = true;
template<class T1, class T2>
void pr(const pair<T1, T2> &x);
template<class T, size_t SZ>
void pr(const array<T, SZ> &x);
template<class T>
void pr(const vector<T> &x);
template<class T>
void pr(const set<T> &x);
template<class T1, class T2>
void pr(const map<T1, T2> &x);
template<class T>
void pr(const T &x) { if (DEBUG) cout << x; }
template<class T, class... Ts>
void pr(const T &first, const Ts &... rest) { pr(first), pr(rest...); }
template<class T1, class T2>
void pr(const pair<T1, T2> &x) { pr("{", x.f, ", ", x.s, "}"); }
template<class T>
void prIn(const T &x) {
pr("{");
bool fst = 1;
for (auto &a : x) {
pr(fst ? "" : ", ", a), fst = 0;
}
pr("}");
}
template<class T, size_t SZ>
void pr(const array<T, SZ> &x) { prIn(x); }
template<class T>
void pr(const vector<T> &x) { prIn(x); }
template<class T>
void pr(const set<T> &x) { prIn(x); }
template<class T1, class T2>
void pr(const map<T1, T2> &x) { prIn(x); }
void ps() { pr("\n"), cout << flush; }
template<class Arg, class... Args>
void ps(const Arg &first, const Args &... rest) {
pr(first, " ");
ps(rest...);
}
}
using namespace debug;
const int MAXN = 5e5 + 100;
const int INF = 1e9;
struct SegTr {
int tr[4 * MAXN];
void b(int i, int l, int r) {
if (l == r) {
tr[i] = -INF;
return;
}
int mid = (l + r) / 2;
b(i * 2, l, mid);
b(i * 2 + 1, mid + 1, r);
tr[i] = max(tr[i * 2], tr[i * 2 + 1]);
}
int q(int i, int l, int r, int s, int e) {
if (e < l || r < s) {
return -INF;
}
if (s <= l && r <= e) {
return tr[i];
}
int mid = (l + r) / 2;
return max(q(i * 2, l, mid, s, e), q(i * 2 + 1, mid + 1, r, s, e));
}
void u(int i, int l, int r, int x, int d) {
if (l == r) {
tr[i] = max(tr[i], d);
return;
}
int mid = (l + r) / 2;
if (x <= mid) {
u(i * 2, l, mid, x, d);
} else {
u(i * 2 + 1, mid + 1, r, x, d);
}
tr[i] = max(tr[i * 2], tr[i * 2 + 1]);
}
} dTr, uTr;
int N, U, D, S;
vector<pi> fairs[MAXN];
int main() {
// ps("start");
cin >> N >> U >> D >> S;
U = -U, D = -D; // let change in value = negative coefficient * distance
for (int i = 0; i < N; i++) {
int t, l, v;
cin >> t >> l >> v;
fairs[t].pb({l, v});
}
// ps("read");
for (int i = 0; i < MAXN; i++) {
sort(fairs[i].begin(), fairs[i].end());
// ps(i);
}
// ps("sorted");
dTr.b(1, 1, MAXN);
uTr.b(1, 1, MAXN);
dTr.u(1, 1, MAXN, S, S * D); // down update = positive
uTr.u(1, 1, MAXN, S, -S * U); // up update = negative
for (int cT = 0; cT < MAXN; cT++) {
if (fairs[cT].empty()) {
continue;
}
// ps("cT:", cT);
vector<pi> &cF = fairs[cT];
vi sVal(cF.size(), -INF), bVal(cF.size(), -INF);
for (int i = 0; i < cF.size(); i++) {
int dVal = dTr.q(1, 1, MAXN, cF[i].f, MAXN) - cF[i].f * D;
int uVal = uTr.q(1, 1, MAXN, 1, cF[i].f) + cF[i].f * U;
sVal[i] = max(dVal, uVal) + cF[i].s;
}
int prev = -INF;
for (int i = 0; i < cF.size(); i++) {
int cur = (i == 0) ? -INF : prev + (cF[i].f - cF[i - 1].f) * U + cF[i].s;
cur = max(cur, sVal[i]);
bVal[i] = max(bVal[i], cur);
prev = cur;
}
prev = -INF;
for (int i = cF.size() - 1; i >= 0; i--) {
int cur = (i == cF.size() - 1) ? -INF : prev + (cF[i + 1].f - cF[i].f) * D + cF[i].s;
cur = max(cur, sVal[i]);
bVal[i] = max(bVal[i], cur);
prev = cur;
}
for (int i = 0; i < cF.size(); i++) {
dTr.u(1, 1, MAXN, cF[i].f, bVal[i] + cF[i].f * D);
uTr.u(1, 1, MAXN, cF[i].f, bVal[i] - cF[i].f * U);
}
}
int dAns = dTr.q(1, 1, MAXN, S, MAXN) - S * D;
int uAns = uTr.q(1, 1, MAXN, 1, S) + S * U;
int ans = max(dAns, uAns);
cout << ans << endl;
}
