#include <bits/stdc++.h>
#define POS first
#define VAL second
using namespace std;
using ll = long long;
using vpi = vector<pair<ll, ll>>;
const int MAX = 500009;
const ll INF = 0x3f3f3f3f;
vpi arr[MAX];
ll n, u, d, s;
ll tree_u[2*MAX], tree_d[2*MAX];
ll getMax(ll *arr, ll l, ll r) {
ll ret = -INF;
for(l += MAX, r += MAX; l<=r; l>>=1, r>>=1) {
if(l&1) ret = max(ret, arr[l++]);
if(~r&1) ret = max(ret, arr[r--]);
}
return ret;
}
void update(ll *arr, ll idx, ll val) {
idx += MAX;
arr[idx] = max(arr[idx], val);
for(;idx>1;idx>>=1) {
arr[idx>>1] = max(arr[idx], arr[idx^1]);
}
}
void updateUD(ll idx, ll val) {
update(tree_u, idx, val - u * idx);
update(tree_d, idx, val + d * idx);
}
ll getDP(ll idx) {
return max(getMax(tree_d, 0, idx) - d * idx, getMax(tree_u, idx, MAX-1) + u*idx);
}
ll i;
void query_market(vpi &market) {
ll j = 0;
if(market.size() == 0) { return; }
sort(market.begin(), market.end());
vector<ll> up, down;
ll sz = market.size();
for(j=0; j<sz; j++) {
ll tmp = getDP(market[j].POS);
up.push_back(tmp);
down.push_back(tmp);
}
for(j=0; j<sz; j++) {
if(j != 0) { down[j] = max(down[j], down[j-1] - d * (market[j].POS - market[j-1].POS));}
down[j] += market[j].VAL;
}
for(j=sz-1; j>=0; j--) {
if(j != sz-1) { up[j] = max(up[j], up[j-1] - u * (market[j+1].POS - market[j].POS)); }
up[j] += market[j].VAL;
}
for(j=0; j<sz; j++) {
updateUD(market[j].POS, max(up[j], down[j]));
}
}
void fastIO() {
ios::sync_with_stdio(false); cin.tie(0);
}
void input() {
scanf("%lld %lld %lld %lld",&n,&u,&d,&s);
ll a, b, c;
for(int x = 0; x<n; x++) {
scanf("%lld %lld %lld",&a,&b,&c);
arr[a].push_back({b, c});
}
}
void solve() {
memset(tree_u, 0xc0, sizeof(tree_u));
memset(tree_d, 0xc0, sizeof(tree_d));
updateUD(s, 0);
for(i=1; i<=500001; i++) {
query_market(arr[i]);
}
printf("%lld",getDP(s));
}
int main() {
fastIO();
input();
solve();
return 0;
}
