#define _CRT_SECURE_NO_WARNINGS
#ifdef _DEBUG
#define FILE_IN "input.txt"
#define FILE_OUT "output.txt"
#endif
#include <iostream>
#include <cstdlib>
#include <climits>
#include <set>
#include <map>
#include <cstdio>
#include <string>
#include <cstring>
#include <cassert>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
typedef long long ll;
void openFiles() {
#ifdef _DEBUG
assert(freopen(FILE_IN, "r", stdin));
assert(freopen(FILE_OUT, "w", stdout));
#endif
}
vector<ll> a;
const int MAXN = 200000 + 10;
ll t[4 * MAXN];
ll add[4 * MAXN];
int n, q, s_up, s_down;
void push(int x, int l, int r) {
t[x] += (r - l) * add[x];
if (r - l > 1) {
add[2 * x + 1] += add[x];
add[2 * x + 2] += add[x];
}
add[x] = 0;
}
void update(int x, int l, int r, int ql, int qr, ll val) {
push(x, l, r);
if (l >= qr || r <= ql)
return;
if (ql <= l && r <= qr) {
add[x] += val;
push(x, l, r);
return;
}
int c = (l + r) / 2;
update(2 * x + 1, l, c, ql, qr, val);
update(2 * x + 2, c, r, ql, qr, val);
t[x] = t[2 * x + 1] + t[2 * x + 2];
}
ll query(int x, int l, int r, int ql, int qr) {
push(x, l, r);
if (l >= qr || r <= ql)
return 0LL;
if (ql <= l && r <= qr) {
return t[x];
}
int c = (l + r) / 2;
return (
query(2 * x + 1, l, c, ql, qr) +
query(2 * x + 2, c, r, ql, qr)
);
}
ll get_a(int i) {
return query(0, 0, n, i, i + 1);
}
ll sign(ll f) {
if (f == 0)
return 1;
return (f) / abs(f);
}
int main() {
openFiles();
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> q >> s_up >> s_down;
n++;
a.resize(n);
for (int i = 0; i < n; i++) {
cin >> a[i];
update(0, 0, n, i, i + 1, a[i]);
}
ll up_cnt = 0, down_cnt = 0;
for (int i = 1; i < n; i++) {
if (a[i] > a[i - 1]) {
up_cnt += a[i] - a[i - 1];
}
else {
down_cnt += a[i - 1] - a[i];
}
}
for (int j = 0; j < q; j++) {
/*for (int i = 0; i < n; i++)
cout << get_a(i) << " ";
cout << "\n";*/
int l, r;
ll x;
cin >> l >> r >> x;
ll left_dist = get_a(l) - get_a(l - 1);
ll right_dist;
if (r != n - 1) {
right_dist = get_a(r + 1) - get_a(r);
}
update(0, 0, n, l, r + 1, x);
ll new_left_dist = get_a(l) - get_a(l - 1);
ll new_right_dist;
if (r != n - 1) {
new_right_dist = get_a(r + 1) - get_a(r);
}
if (sign(new_left_dist) == sign(left_dist)) {
if (sign(left_dist) == 1) {
up_cnt += x;
}
else {
down_cnt -= x;
}
}
else {
if (sign(left_dist) == 1) {
up_cnt -= left_dist;
down_cnt += -new_left_dist;
}
else {
down_cnt -= -left_dist;
up_cnt += new_left_dist;
}
}
if (r != n - 1) {
if (sign(new_right_dist) == sign(right_dist)) {
if (sign(right_dist) == 1) {
up_cnt -= x;
}
else {
down_cnt += x;
}
}
else {
if (sign(right_dist) == 1) {
up_cnt -= right_dist;
down_cnt += -new_right_dist;
}
else {
down_cnt -= -right_dist;
up_cnt += new_right_dist;
}
}
}
ll res = down_cnt * s_down - up_cnt * s_up;
cout << res << "\n";
}
return 0;
}
