#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
int n,u,d,m,s(5e5+1); cin >> n >> u >> d >> m; --m;
vector<vector<pair<int,int>>> A(s); for (int i(0),a,b,c;i < n;++i){
cin >> a >> b >> c; A[a-1].emplace_back(b-1,c);
}
A.back().emplace_back(m,0);
for (auto& B:A) sort(B.begin(),B.end());
vector<int> up(2*s,-1e18),down(2*s,-1e18);
for (int i(s+m);i;i>>=1) up[i] = -u*m,down[i] = -d*(n-m);
auto f = [&](int i) -> int {
int ret = -1e18;
for (int l(s),r(s+i);l < r;l>>=1,r>>=1){
if (l&1) ret = max(ret,down[l++]+d*(n-i));
if (r&1) ret = max(ret,down[--r]+d*(n-i));
}
for (int l(s+i),r(s+s);l < r;l>>=1,r>>=1){
if (l&1) ret = max(ret,up[l++]+u*i);
if (r&1) ret = max(ret,up[--r]+u*i);
}
return ret;
};
for (auto& B:A){
int q = B.size(); vector<int> C(q),D(q);
for (int i(0);i < q;++i){
C[i] = f(B[i].first)+B[i].second;
if (i) C[i] = max(C[i],C[i-1]+B[i].second);
}
for (int i(q-1);i > -1;--i){
D[i] = f(B[i].first)+B[i].second;
if (i!=q-1) D[i] = max(D[i],D[i+1]+B[i].second);
}
for (int i(0);i < q;++i) for (int k(s+B[i].first);k;k>>=1){
up[k] = max(up[k],max(C[i],D[i])-u*B[i].first);
down[k] = max(down[k],max(C[i],D[i])-d*(n-B[i].first));
}
}
cout << up[s+m]+u*m << endl;
}
