#include<bits/stdc++.h>
#define int long long
#define bl bool
#define db double
#define fl float
#define st string
#define pb push_back
#define pf push_front
#define is insert
#define endl "\n"
#define pba pop_back
#define pfr pop_front
#define ub upper_bound
#define lb lower_bound
#define fi first
#define se second
#define FOR(i, l, r, st) for(int i = l; i <= r; i += st)
#define FOS(i, l, r, sl) for(int i = l; i >= r; i -= sl)
#define mii map<int, int>
#define us unordered_set
#define pii pair<int, int>
#define vt vector
using namespace std;
const int maxn = 1e6 + 5;
const int mod = 1e9 + 7;
struct SEG{
int seg[4 * maxn], lz[4 * maxn];
void inp() {
memset(seg, 0, sizeof(seg));
memset(lz, 0, sizeof(lz));
}
void push(int id, int l, int r) {
if(lz[id] != 0) {
seg[id] = seg[id] + lz[id] * (r - l + 1);
if(l != r) {
lz[2 * id] += lz[id];
lz[2 * id + 1] += lz[id];
}
lz[id] = 0;
}
}
void up(int id, int l, int r, int lr, int rr, int val) {
push(id, l, r);
if(lr > r || rr < l) return;
if(lr <= l && r <= rr) {
lz[id] += val;
push(id, l, r);
return;
}
int mid = (l + r) / 2;
up(2 * id, l, mid, lr, rr, val);
up(2 * id + 1, mid + 1, r, lr, rr, val);
seg[id] = seg[2 * id] + seg[2 * id + 1];
}
int get(int id, int l, int r, int pos) {
push(id, l, r);
if(l > pos || r < pos) return 0;
if(l == r) return seg[id];
int mid = (l + r) / 2;
if(pos <= mid) return get(2 * id, l, mid, pos);
else return get(2 * id + 1, mid + 1, r, pos);
}
} seg;
int n, q, s, t, a[maxn];
int rep(int l, int r) {
if(l >= r) return ((l - r) * t);
else return -((r - l) * s);
}
main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
seg.inp();
cin >> n >> q >> s >> t;
int res = 0;
FOR(i, 0, n, 1) cin >> a[i];
FOR(i, 0, n - 1, 1) res += rep(a[i], a[i + 1]);
while(q --) {
int l, r, val; cin >> l >> r >> val;
int lef1 = a[l - 1] + seg.get(1, 0, n, l - 1);
int lef2 = a[l] + seg.get(1, 0, n, l);
res -= rep(lef1, lef2);
if(r < n) {
int rit1 = a[r] + seg.get(1, 0, n, r);
int rit2 = a[r + 1] + seg.get(1, 0, n, r + 1);
res -= rep(rit1, rit2);
}
seg.up(1, 0, n, l, r, val);
lef1 = a[l - 1] + seg.get(1, 0, n, l - 1);
lef2 = a[l] + seg.get(1, 0, n, l);
res += rep(lef1, lef2);
if(r < n) {
int rit1 = a[r] + seg.get(1, 0, n, r);
int rit2 = a[r + 1] + seg.get(1, 0, n, r + 1);
res += rep(rit1, rit2);
}
cout << res << endl;
}
}
