#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define ordered_set <int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define ordered_multiset <int, null_type, less_equal <int>, rb_tree_tag, tree_order_statistics_node_update>
#define int long long
#define double long double
#define pii pair <int, int>
#define tiii tuple <int, int, int>
#define tiiii tuple <int, int, int, int>
#define emb emplace_back
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define iShowSpeed cin.tie(NULL)->sync_with_stdio(false)
#define matrix vector <vector <int>>
#define mat(n, m) vector <vector <int>> (n, vector <int> (m));
const int mod = 1e9 + 7;
const int inf = 1e18;
const matrix II = {{1, 0}, {0, 1}};
const int N = 2e5 + 5;
int a[N], temp[N];
struct {
int seg[4 * N], lazy[4 * N];
void push(int l, int r, int i){
seg[i] += lazy[i] * (r - l + 1);
if (l != r) lazy[2 * i] += lazy[i], lazy[2 * i + 1] += lazy[i];
lazy[i] = 0;
}
void build(int l, int r, int i){
if (l == r) return seg[i] = temp[l], void();
int mid = (l + r) / 2;
build(l, mid, 2 * i), build(mid + 1, r, 2 * i + 1);
seg[i] = seg[2 * i] + seg[2 * i + 1];
}
void update(int l, int r, int i, int ll, int rr, int val){
push(l, r, i);
if (l >= ll && r <= rr) return lazy[i] += val, push(l, r, i), void();
if (r < ll || l > rr) return;
int mid = (l + r) / 2;
update(l, mid, 2 * i, ll, rr, val), update(mid + 1, r, 2 * i + 1, ll, rr, val);
seg[i] = seg[2 * i] + seg[2 * i + 1];
}
int query(int l, int r, int i, int idx){
push(l, r, i);
if (l == r) return seg[i];
int mid = (l + r) / 2;
if (idx <= mid) return query(l, mid, 2 * i, idx);
else return query(mid + 1, r, 2 * i + 1, idx);
}
} seg;
void solve(){
int n, q, s, t; cin >> n >> q >> s >> t;
for (int i = 0; i <= n; i++) cin >> a[i];
for (int i = 1; i <= n; i++) temp[i] = temp[i - 1] + (a[i - 1] < a[i] ? s * (a[i - 1] - a[i]) : t * (a[i - 1] - a[i]));
seg.build(1, n, 1);
while (q--) {
int l, r, x; cin >> l >> r >> x;
int dif = seg.query(1, n, 1, l) - (l == 1 ? 0ll : seg.query(1, n, 1, l - 1));
int dh = 0;
if (dif > 0) dh = -dif / t;
else dh = -dif / s;
dh += x;
int newdif = (dh < 0 ? -dh * t : -dh * s);
if (r < n) {
int rdif = seg.query(1, n, 1, r + 1) - seg.query(1, n, 1, r);
int rdh = 0;
if (rdif > 0) rdh = -rdif / t;
else rdh = -rdif / s;
rdh -= x;
int newrdif = (rdh < 0 ? -rdh * t : -rdh * s);
seg.update(1, n, 1, r + 1, n, newrdif - rdif);
}
seg.update(1, n, 1, l, n, newdif - dif);
cout << seg.query(1, n, 1, n) << "\n";
}
}
int32_t main(){
iShowSpeed;
// int q; cin >> q; while (q--)
solve();
}
