#include <iostream>
#include <fstream>
#include <cstring>
#include <sstream>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <iterator>
#include <ext/pb_ds/assoc_container.hpp>
#define x first
#define y second
#define mp make_pair
#define up_b upper_bound
#define low_b lower_bound
#define sz(x) (int)x.size()
#define bit __builtin_popcount
#define all(x) x.begin(),x.end()
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
typedef pair<int,ll> pil;
typedef pair<ll,int> pli;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> indexed_set;
const ll INF=1e18+123;
const ld EPS=1e-9;
const int inf=1e9+123;
const int MOD=1e9+7;
const int N=2e5+123;
const int dx[]={0ll,0ll,1,-1};
const int dy[]={1,-1,0ll,0ll};
ll a[N],x[N];
int main(){
ios_base::sync_with_stdio(0ll);
cin.tie(0ll);
int n,q;
ll s,t;
cin>>n>>q>>s>>t;
ll ans=0ll;
cin>>a[0ll];
for(int i=1;i<=n;i++){
cin>>a[i];
x[i]=-a[i]+a[i-1];
ans+=1ll*s*min(x[i],0ll);
ans+=1ll*t*max(x[i],0ll);
}
int l,r,c;
while(q--){
cin>>l>>r>>c;
r++;
if(l<=n){
ans-=s*min(x[l],0ll);
ans-=t*max(x[l],0ll);
x[l]-=c;
ans+=s*min(x[l],0ll);
ans+=t*max(x[l],0ll);
}
if(r<=n){
ans-=s*min(x[r],0ll);
ans-=t*max(x[r],0ll);
x[r]+=c;
ans+=s*min(x[r],0ll);
ans+=t*max(x[r],0ll);
}
cout<<ans<<endl;
}
return 0ll;
}
