#include <bits/stdc++.h>
using namespace std;
int n, u, d, s;
const int I = 0, F = 500002;
struct Fair {int t, l, m;};
bool comp(Fair A, Fair B) {return A.t < B.t;}
int price(int a, int b) {return max((b-a)*d, (b-a)*(-u));}
struct Segtree {
int n;
vector<int> st;
Segtree(int n) : n(n), st(vector<int>(4*n, -2e9)) {};
void update(int p, int l, int r, int i, int x) {
if (l == r) st[p] = x;
else {
int m = (l+r)/2;
if (i <= m) update(2*p, l, m, i, x);
else update(2*p+1, m+1, r, i, x);
st[p] = max(st[2*p], st[2*p+1]);
}
}
int Max(int p, int l, int r, int i, int j) {
if (i > j) return -2e9;
else if (i == l && j == r) return st[p];
int m = (l+r)/2;
return max(Max(2*p, l, m, i, min(m, j)), Max(2*p+1, m+1, r, max(i, m+1), j));
}
void update(int i, int x) {update(1, 0, n-1, i, x);}
int Max(int i, int j) {return Max(1, 0, n-1, i, j);}
};
map<int, int> cmpr;
map<int, int> inv_cmpr;
void coordinate_compression(vector<Fair>& fairs) {
set<int> values;
for (int i = 0; i < n; ++i) values.insert(fairs[i].l);
int cnt = 0;
for (int v: values) {
cmpr[v] = cnt;
inv_cmpr[cnt] = v;
++cnt;
}
}
signed main() {
cin >> n >> u >> d >> s;
vector<Fair> fairs(n);
for (int i = 0; i < n; ++i) cin >> fairs[i].t >> fairs[i].l >> fairs[i].m;
sort(fairs.begin(), fairs.end(), comp);
coordinate_compression(fairs);
Segtree StU(n), StD(n);
vector<int> dp(n);
for (int i = n-1; i >= 0; --i) {
dp[i] += fairs[i].m;
int aux = StU.Max(0, cmpr[fairs[i].l]-1)+(F-fairs[i].l)*u;
aux = max(aux, StD.Max(cmpr[fairs[i].l]+1, n-1)+fairs[i].l*d);
aux = max(aux, -price(fairs[i].l, s));
dp[i] += aux;
StU.update(cmpr[fairs[i].l], dp[i]-(F-fairs[i].l)*u);
StD.update(cmpr[fairs[i].l], dp[i]-fairs[i].l*d);
}
int ans = 0;
for (int i = 0; i < n; ++i) ans = max(ans, dp[i]-price(s, fairs[i].l));
cout << ans << endl;
return 0;
}
