#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 3e5 + 30, MOD = 1e9 + 7;
#define int ll
int n,a[N],q,s,f;
ll all = 0,add[N * 4];
struct node{
ll sum = 0,l = 0,r = 0;
bool empty = false;
}t[N * 4];
node merge(node a,node b){
if(a.empty) return b;
if(b.empty) return a;
a.sum += b.sum;
if(a.r < b.l){
a.sum -= (b.l - a.r) * s;
}else{
a.sum += (a.r - b.l) * f;
}
a.r = b.r;
return a;
}
void build(int v = 1,int tl = 1,int tr = n){
if(tl == tr){
t[v].l = t[v].r = a[tl];
t[v].sum = 0;
}else{
int tm = (tl + tr) >> 1;
build(v + v,tl,tm);
build(v + v + 1,tm + 1,tr);
t[v] = merge(t[v + v],t[v + v + 1]);
}
}
void inc(int v,int val){
t[v].l += val;
t[v].r += val;
add[v] += val;
}
void push(int v){
if(add[v]){
inc(v + v,add[v]);
inc(v + v + 1,add[v]);
add[v] = 0;
}
}
void upd(int l,int r,int val,int v = 1,int tl = 1,int tr = n){
if(l > r || tl > r || l > tr) return;
if(tl >= l && tr <= r){
inc(v,val);
}else{
push(v);
int tm = (tl + tr) >> 1;
upd(l,r,val,v+v,tl,tm);
upd(l,r,val,v+v+1,tm+1,tr);
t[v] = merge(t[v + v],t[v + v + 1]);
}
}
void test(){
cin >> n >> q >> s >> f;
n++;
for(int i = 1;i <= n;i++){
cin >> a[i];
}
build();
// cout << t[1].sum << '\n';
while(q--){
int l,r,x;
cin >> l >> r >> x;
l++;r++;
// cout << l << ' ' << r << ' ' << x << '\n';
upd(l,r,x);
cout << t[1].sum << '\n';
}
}
signed main() {
ios_base::sync_with_stdio(false);cin.tie(0);
int t = 1;
// cin >> t;
while(t--){
test();
}
}
