#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
#define pb push_back
#define f first
#define s second
const int MAXN = 2e5 + 10;
ll d[MAXN];
int N, Q;
ll S, T;
ll cost = 0;
void update(ll d, int x) {
if (d > 0) {
cost -= d * S * x;
} else {
cost += abs(d) * T * x;
}
}
int main() {
cin >> N >> Q >> S >> T;
int last = 0;
cin >> last;
assert(last == 0);
for (int i = 0; i < N; i++) {
int c;
cin >> c;
d[i] = c - last;
last = c;
}
for (int i = 0; i < N; i++) {
update(d[i], 1);
}
// cout << cost << endl;
for (int i = 0; i < Q; i++) {
int l, r, x;
cin >> l >> r >> x;
l--;
update(d[l], -1);
d[l] += x;
update(d[l], 1);
if (r < N) {
update(d[r], -1);
d[r] -= x;
update(d[r], 1);
}
// for (int i = 0; i < N; i++) {
// cout << d[i] << " ";
// }
// cout << endl;
cout << cost << endl;
}
}
