#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,sse,sse2")
#include<bits/stdc++.h>
#define all(x) begin(x), end(x)
using namespace std;
const int maxn =5e5 + 15, C = 1;
using ll = long long;
const ll inf = 1ll<<55;
struct segtree {
vector<ll> t;
int n;
segtree(int n) : n(n), t(2*n, -inf) {}
void update(int pos, ll val) {
t[pos+n] = max(t[pos+n], val);
for(pos+=n;pos/=2;) t[pos] = max(t[2*pos], t[2*pos+1]);
}
ll query(int l, int r) {
ll ans = -inf;
for(l+=n,r+=n;l<r;l>>=1,r>>=1) {
if(l&1) ans = max(ans, t[l++]);
if(r&1) ans = max(ans, t[--r]);
}
return ans;
}
};
int n, s;
ll u, d;
segtree down(maxn), up(maxn);
vector<array<int, 2>> cur[maxn];
void upd(int pos, ll val) {
down.update(pos, val - d*pos);
up.update(pos, val + u*pos);
}
int main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n >> d >> u >> s;
upd(s, 0);
for(int d, l, c, i = 0; i < n; i++) {
cin >> d >> l >> c;
cur[d].push_back({l, c});
}
for(int day = 0; day < maxn; day++) if(!cur[day].empty()) {
n = cur[day].size();
sort(all(cur[day]));
vector<ll> dp_down(n), dp_up(n);
for(int i = 0; i < n; i++) {
dp_down[i] = max(-inf, down.query(cur[day][i][0], maxn) + cur[day][i][0]*d);
}
for(int i = 0; i < n; i++) {
if(i) dp_down[i] = max(dp_down[i], dp_down[i-1] - u*(cur[day][i][0]-cur[day][i-1][0]));
dp_down[i] += cur[day][i][1];
}
for(int i = 0; i < n; i++) {
dp_up[i] = max(-inf, up.query(0, cur[day][i][0]) - cur[day][i][0]*u);
}
for(int i = n; i--;) {
if(i+1<n) dp_up[i] = max(dp_up[i], dp_up[i+1] - d*(cur[day][i+1][0]-cur[day][i][0]));
dp_up[i] += cur[day][i][1];
}
for(int i = 0; i < n; i++) {
upd(cur[day][i][0], max(dp_down[i], dp_up[i]));
}
}
ll res = max(up.query(0, s) - u*s, down.query(s, maxn) + d*s);
cout << res << '\n';
}
