/**
* author: AgentPengin ( Độc cô cầu bại )
* created: 23.12.2022 10:08:02
* too lazy to update time
**/
#include<bits/stdc++.h>
#define EL '\n'
#define fi first
#define se second
#define NAME "TASK"
#define ll long long
#define lcm(a,b) (a/gcd(a,b))*b
#define db(val) "["#val" = " << (val) << "] "
#define bend(v) (v).begin(),(v).end()
#define sz(v) (int)(v).size()
#define ex exit(0)
#define int ll
using namespace std;
const ll mod = 1e9 + 7;
const int inf = 0x1FFFFFFF;
const int MAXN = 2e5 + 5;
int n,q,S,T,a[MAXN];
struct Node {
int sum,lazy;
} st[MAXN << 2];
void build(int id = 1,int l = 0,int r = n) {
if (l > r) return;
if (l == r) {
st[id].sum = a[l];
return;
}
int mid = l + r >> 1;
build(id << 1, l, mid);
build(id << 1 | 1, mid + 1, r);
st[id].sum = st[id << 1].sum + st[id << 1 | 1].sum;
}
void pushDown(int id, int l, int r) {
st[id].sum += st[id].lazy * (r - l + 1);
if (l != r) {
st[id << 1].lazy += st[id].lazy;
st[id << 1 | 1].lazy += st[id].lazy;
}
st[id].lazy = 0;
}
void update(int u,int v, int val, int id = 1, int l = 0, int r = n) {
pushDown(id, l, r);
if (v < l || u > r) return;
if (u <= l && r <= v) {
st[id].lazy += val;
pushDown(id, l, r);
return;
}
pushDown(id, l, r);
int mid = l + r >> 1;
update(u, v, val, id << 1, l, mid);
update(u, v, val, id << 1 | 1, mid + 1, r);
st[id].sum = st[id << 1].sum + st[id << 1 | 1].sum;
}
int get(int u,int v, int id = 1, int l = 0,int r = n) {
pushDown(id, l , r);
if (v < l || u > r) return 0;
if (u <= l && r <= v) {
return st[id].sum;
}
int mid = l + r >> 1;
return get(u, v, id << 1, l, mid) + get(u, v, id << 1 | 1,mid + 1,r);
}
signed main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
if (ifstream(NAME".inp")) {
freopen(NAME".inp","r",stdin);
freopen(NAME".out","w",stdout);
}
cin >> n >> q >> S >> T;
for (int i = 0;i <= n;i++) {
cin >> a[i];
}
build();
int temp = 0;
for (int i = 1;i <= n;i++) {
if (a[i] <= a[i - 1]) temp += T * abs(a[i - 1] - a[i]);
else temp -= S * abs(a[i] - a[i - 1]);
}
// 4 * 1 - 2 + 5
while(q--) {
int l, r, x;
cin >> l >> r >> x;
int pos_l_1 = get(l - 1, l - 1);
int pos_l = get(l, l);
if (pos_l_1 >= pos_l) temp -= T * abs(pos_l_1 - pos_l);
else temp += S * abs(pos_l_1 - pos_l);
int pos_r = get(r, r);
int pos_r_1 = get(r + 1, r + 1);
if (r != n && pos_r >= pos_r_1) temp -= T * abs(pos_r - pos_r_1);
else if (r != n) temp += S * abs(pos_r - pos_r_1);
update(l, r, x);
pos_l_1 = get(l - 1, l - 1);
pos_l = get(l, l);
if (pos_l_1 >= pos_l) temp += T * abs(pos_l_1 - pos_l);
else temp -= S * abs(pos_l_1 - pos_l);
pos_r = get(r, r);
pos_r_1 = get(r + 1, r + 1);
if (r != n && pos_r >= pos_r_1) temp += T * abs(pos_r - pos_r_1);
else if (r != n) temp -= S * abs(pos_r - pos_r_1);
cout << temp << '\n';
}
cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
return 0;
}
// agent pengin wants to take apio (with anya-san)
