#include <bits/stdc++.h>
using namespace std;
#define int long long
int n, q, s, t;
long long a[200005];
long long it[800005], lazy[800005];
long long res = 0;
void init(int k, int l, int r)
{
if (l == r)
{
it[k] = a[l];
return;
}
int mid = (l + r)/2;
init(k * 2, l, mid);
init(k * 2 + 1, mid+1, r);
it[k] = it[k * 2] + it[k * 2 + 1];
}
void update(int k, int l, int r, int L, int R, int val)
{
if (l > R || r < L) return;
if (L <= l && R >= r)
{
it[k] += val * (r - l + 1);
lazy[k] += val;
return;
}
int mid = (l+r) / 2;
int t = lazy[k];
lazy[k * 2] += t;
lazy[k * 2 + 1] += t;
it[k * 2] += t * (mid - l + 1);
it[k * 2 + 1] += t * (r - mid);
lazy[k] = 0;
update(k * 2, l, mid, L, R, val);
update(k * 2 + 1, mid + 1, r, L, R, val);
it[k] = it[k * 2] + it[k * 2 + 1];
}
long long get(int k, int l, int r, int L, int R)
{
if (R < l || L > r) return 0ll;
if (L <= l && r <= R) {
return it[k];
}
int mid = (l+r) / 2;
int t = lazy[k];
lazy[k * 2] += t;
lazy[k * 2 + 1] += t;
it[k * 2] += t * (mid - l + 1);
it[k * 2 + 1] += t * (r - mid);
lazy[k] = 0;
return get(k * 2, l, mid, L, R) + get(k * 2 + 1, mid + 1, r, L, R);
}
void in()
{
scanf("%lld%lld%lld%lld", &n, &q, &s, &t);
for (int i = 0; i <= n; i++)
{
scanf("%lld", &a[i]);
}
}
void ou()
{
printf("%lld\n", res);
}
void solve()
{
init(1, 1, n);
for (int i = 1; i <= n; i++)
{
res += (a[i-1] - a[i] < 0) ? (s * (a[i-1] - a[i])) : (t * (a[i-1] - a[i]));
}
for (int i = 1; i <= q; i++)
{
int l, r, x;
scanf("%lld%lld%lld", &l, &r, &x);
long long precl, precr;
precl = get(1, 1, n, l, l);
precr = get(1, 1, n, r, r);
update(1, 1, n, l, r, x);
long long curl = get(1, 1, n, l, l);
long long curr = get(1, 1, n, r, r);
long long re1 = 0, re2 = 0;
a[l - 1] = get(1, 1, n, l-1, l-1);
re1 += (a[l-1] - precl < 0) ? (s * (a[l-1] - precl)) : (t * (a[l-1] - precl));
re2 += (a[l-1] - curl < 0) ? (s * (a[l-1] - curl)) : (t * (a[l-1] - curl));
if (r < n)
{
a[r+1] = get(1, 1, n, r+1, r+1);
re1 += (precr - a[r+1] < 0) ? (s * (precr - a[r+1])) : (t * (precr - a[r+1]));
re2 += (curr - a[r+1] < 0) ? (s * (curr - a[r+1])) : (t * (curr - a[r+1]));
}
res += re2 - re1;
ou();
}
}
signed main()
{
in();
solve();
}
