#include <bits/stdc++.h>
using namespace std;
const int MAXN = 500009;
const int INF = 0x3f3f3f3f;
typedef pair<int,int> pii;
typedef vector<pair<int,int> > vpi;
vpi mark[MAXN];
int n,u,d,s,uptree[2*MAXN],downtree[2*MAXN];
int query(int *arr,int l,int r)
{
int ans=-INF;
for(l+=MAXN,r+=MAXN;l<=r;l>>=1,r>>=1)
{
if(l&1) ans=max(ans,arr[l++]);
if(~r&1) ans=max(ans,arr[r--]);
}
return ans;
}
void update(int *arr,int x,int v)
{
x+=MAXN;
arr[x]=max(arr[x],v);
for(;x>1;x>>=1) arr[x>>1]=max(arr[x],arr[x^1]);
}
void updatep(int x,int v)
{
update(uptree,x,v-u*x);
update(downtree,x,v+d*x);
}
int realquery(int a)
{
return max(query(downtree,0,a)-d*a,query(uptree,a,MAXN-1)+u*a);
}
void markt(vpi &market)
{
if(market.size()==0) return;
sort(market.begin(),market.end());
vector<int> U,D;
int sz=market.size();
for(int i=0;i<sz;i++)
{
int temp=realquery(market[i].first);
U.push_back(temp),D.push_back(temp);
}
for(int i=0;i<sz;i++)
{
if(i!=0) D[i]=max(D[i],D[i-1]-d*(market[i].first-market[i-1].first));
D[i]+=market[i].second;
}
for(int i=sz-1;i>=0;i--)
{
if(i!=sz-1) U[i]=max(U[i],U[i+1]-u*(market[i+1].first-market[i].first));
U[i]+=market[i].second;
}
for(int i=0;i<sz;i++) updatep(market[i].first,max(U[i],D[i]));
}
int main()
{
scanf("%d %d %d %d",&n,&u,&d,&s);
for(int i=0,x,y,z;i<n;i++)
{
scanf("%d %d %d",&x,&y,&z);
mark[x].push_back(make_pair(y,z));
}
memset(uptree,0xc0,sizeof(uptree));
memset(downtree,0xc0,sizeof(downtree));
updatep(s,0);
for(int i=1;i<=500001;i++) markt(mark[i]);
return !printf("%d",realquery(s));
}
