#include <bits/stdc++.h>
using namespace std;
#define int long long
#define maxn 200050
vector<int> seg(maxn*4,0),lazy(maxn*4,0);
vector<int> vect1;
void build(int node,int start,int end){
if(start==end){
seg[node] = vect1[start];
return;
}
int mid = (start+end)/2;
build(node*2+1,start,mid);
build(node*2+2,mid+1,end);
}
void update(int node,int start,int end,int rangemin,int rangemax,int val){
if(lazy[node]!=0){
seg[node] += lazy[node];
if(start!=end){
lazy[node*2+1] += lazy[node];
lazy[node*2+2] += lazy[node];
}
lazy[node] = 0;
}
if(start>rangemax||end<rangemin){
return;
}
else if(start>=rangemin&&end<=rangemax){
seg[node] += val;
if(start!=end){
lazy[node*2+1] += val;
lazy[node*2+2] += val;
}
return;
}
int mid = (start+end)/2;
update(node*2+1,start,mid,rangemin,rangemax,val);
update(node*2+2,mid+1,end,rangemin,rangemax,val);
seg[node] = seg[node*2+1]+seg[node*2+2];
}
int query(int node,int start,int end,int pos){
if(lazy[node]!=0){
seg[node] += lazy[node];
if(start!=end){
lazy[node*2+1] += lazy[node];
lazy[node*2+2] += lazy[node];
}
lazy[node] = 0;
}
if(start==end&&start==pos){
return seg[node];
}
int mid = (start+end)/2;
if(pos<=mid){
return query(node*2+1,start,mid,pos);
}
else{
return query(node*2+2,mid+1,end,pos);
}
}
int32_t main() {
ios::sync_with_stdio(0);
int no_of_input,no_of_query,up,down;
int input,input1,input2,input3;
cin >> no_of_input >> no_of_query >> up >> down;
for(int i=0;i<=no_of_input;i++){
cin >> input;
vect1.push_back(input);
}
int cntup = 0;
int cntdown = 0;
for(int i=1;i<vect1.size();i++){
if(vect1[i]>vect1[i-1]){
cntup += abs(vect1[i]-vect1[i-1]);
}
else{
cntdown += abs(vect1[i]-vect1[i-1]);
}
}
build(0,0,vect1.size()-1);
//cout << cntup << ' ' << cntdown << "\n";
for(int i=0;i<no_of_query;i++){
cin >> input1 >> input2 >> input3;
//input1--,input2--;
if(input1!=0){
int before = query(0,0,vect1.size()-1,input1-1);
int curr = query(0,0,vect1.size()-1,input1);
if(curr>before){
cntup -= abs(curr-before);
}
else{
cntdown -= abs(curr-before);
}
curr += input3;
if(curr>before){
cntup += abs(curr-before);
}
else{
cntdown += abs(curr-before);
}
}
//cout << cntup << " " << cntdown << "---\n";
if(input2!=vect1.size()-1){
int next = query(0,0,vect1.size()-1,input2+1);
int curr = query(0,0,vect1.size()-1,input2);
if(next>curr){
cntup -= abs(next-curr);
}
else{
cntdown -= abs(next-curr);
}
curr += input3;
if(next>curr){
cntup += abs(next-curr);
}
else{
cntdown += abs(next-curr);
}
}
//cout << cntup << " " << cntdown << "--\n";
update(0,0,vect1.size()-1,input1,input2,input3);
cout << cntdown*down-cntup*up << "\n";
}
}
