#include <bits/stdc++.h>
using namespace std;
struct asdf{
int t, l, m; //time, location, money
bool operator < (asdf &rhs){
return t < rhs.t;
}
};
int dp[505050];
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
int n, u, s, d; cin >> n >> u >> d >> s;
vector<asdf> v(n);
for(int i=0; i<n; i++){
cin >> v[i].t >> v[i].l >> v[i].m;
}
v.push_back({0, s, 0}); //시점
v.push_back({500010, s, 0}); //종점
sort(v.begin(), v.end());
dp[0] = 0;
for(int i=1; i<=n+1; i++){
dp[i] = -1e9;
for(int j=0; j<i; j++){
int dist = abs(v[i].l - v[j].l);
int baseCost = v[i].l >= v[j].l ? u : d;
dp[i] = max(dp[i], dp[j] - dist*baseCost + v[i].m);
}
}
cout << dp[n+1];
}
