#include <bits/stdc++.h>
// #include <ext/rope>
// #include <ext/pb_ds/assoc_container.hpp>
// using namespace __gnu_pbds;
// using namespace __gnu_cxx;
using namespace std;
// #define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ll long long
#define ull unsigned long long
#define ld long double
#define pb push_back
#define bit(mask, i) ((mask >> i) & 1)
#define el '\n'
#define F first
#define S second
template <class X, class Y> bool maximize(X &x, const Y &y) { return (x < y ? x = y, 1 : 0); }
template <class X, class Y> bool minimize(X &x, const Y &y) { return (x > y ? x = y, 1 : 0); }
const int INF = 1e9;
const ll LINF = 1e18;
const int MOD = 1e9 + 7;
const int MULTI = 0;
const ld eps = 1e-9;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0}; // R D L U
const int ddx[4] = {-1, 1, 1, -1}, ddy[4] = {1, 1, -1, -1}; // UR DR DL UL
const char cx[4] = {'R', 'D', 'L', 'U'};
const ll base = 31;
const int nMOD = 2;
const ll mods[] = {(ll)1e9 + 10777, (ll)1e9 + 19777, (ll)1e9 + 3, (ll)1e9 + 3777};
const int maxn = 2e5 + 5;
int n, q, s, t, a[maxn];
ll calc(ll x, ll y) {
return (x < y ? -1LL * s * (y - x) : 1LL * t * (x - y));
}
struct node {
ll diff, fir, lst, lz;
node() : diff(0), fir(0), lst(0), lz(0) {}
} st[4 * maxn];
node merge(node L, node R) {
node res;
res.fir = L.fir; res.lst = R.lst;
res.diff = L.diff + calc(L.lst, R.fir) + R.diff;
return res;
}
struct IT {
void build(int id, int l, int r) {
if (l == r) {
st[id].fir = st[id].lst = a[l];
return;
}
int mid = (l + r) >> 1;
build(id << 1, l, mid);
build(id << 1 | 1, mid + 1, r);
st[id] = merge(st[id << 1], st[id << 1 | 1]);
}
void push(int id) {
ll &t = st[id].lz;
if (t == 0) return;
st[id << 1].fir += t;
st[id << 1].lst += t;
st[id << 1].lz += t;
st[id << 1 | 1].fir += t;
st[id << 1 | 1].lst += t;
st[id << 1 | 1].lz += t;
t = 0;
}
void update(int id, int l, int r, int u, int v, int x) {
if (l == u && r == v) {
st[id].fir += x;
st[id].lst += x;
st[id].lz += x;
return;
}
int mid = (l + r) >> 1; push(id);
if (v <= mid) update(id << 1, l, mid, u, v, x);
else if (u > mid) update(id << 1 | 1, mid + 1, r, u, v, x);
else {
update(id << 1, l, mid, u, mid, x);
update(id << 1 | 1, mid + 1, r, mid + 1, v, x);
}
st[id] = merge(st[id << 1], st[id << 1 | 1]);
}
node get(int id, int l, int r, int u, int v) {
if (l == u && r == v) return st[id];
int mid = (l + r) >> 1; push(id);
if (v <= mid) return get(id << 1, l, mid, u, v);
else if (u > mid) return get(id << 1 | 1, mid + 1, r, u, v);
else return merge(get(id << 1, l, mid, u, mid), get(id << 1 | 1, mid + 1, r, mid + 1, v));
}
} IT;
void solve() {
cin >> n >> q >> s >> t;
for (int i = 0; i <= n; ++i)
cin >> a[i];
IT.build(1, 0, n);
while (q--) {
int l, r, x;
cin >> l >> r >> x;
IT.update(1, 0, n, l, r, x);
cout << st[1].diff << el;
}
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
if (!MULTI) solve();
else {
int test; cin >> test;
while (test--) solve();
}
return 0;
}
