#ifdef LOCAL
#include ".debug.hpp"
#else
#define debug(...) 42
#endif
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
struct Lazy_Segment_Tree {
// update range [l; r] +x, and find sum in range [a; b]
int64_t n;
vector<int64_t> tree, lazy;
Lazy_Segment_Tree(int64_t _n) {
n = _n + 5, tree.assign(n << 2, 0), lazy.assign(n << 2, 0); // init tree and lazy vectors are filled with 0
}
void relax(const int64_t &v, const int64_t &tl, const int64_t &tr) {
if (!lazy[v]) return;
tree[v] += (tr - tl + 1) * lazy[v];
if (tl != tr) lazy[v << 1] += lazy[v], lazy[v << 1 | 1] += lazy[v];
lazy[v] = 0;
}
void update(const int64_t &v, const int64_t &tl, const int64_t &tr, const int64_t &l, const int64_t &r, const int64_t &add) {
relax(v, tl, tr);
if (l > r || tl > r || l > tr) return;
if (l <= tl && tr <= r) {
lazy[v] += add; relax(v, tl, tr);
return;
}
int64_t tm = (tl + tr) >> 1;
update(v << 1, tl, tm, l, min(r, tm), add); update(v << 1 | 1, tm + 1, tr, max(l, tm + 1), r, add);
tree[v] = tree[v << 1] + tree[v << 1 | 1];
}
int64_t getans(const int64_t &v, const int64_t &tl, const int64_t &tr, const int64_t &l, const int64_t &r) {
relax(v, tl, tr);
if (l > r || tl > r || l > tr) return 0;
if (l <= tl && tr <= r) return tree[v];
int64_t tm = (tl + tr) >> 1;
return getans(v << 1, tl, tm, l, min(r, tm)) + getans(v << 1 | 1, tm + 1, tr, max(l, tm + 1), r);
}
};
signed main() {
#ifndef VOID
cin.tie(nullptr)->sync_with_stdio(false);
#endif
int64_t N, Q, S, T, curr = 0; cin >> N >> Q >> S >> T;
Lazy_Segment_Tree segtree(N + 5);
auto cal = [&](const int64_t &val1, const int64_t &val2) -> int64_t {
return (val1 - val2) * (val2 > val1 ? S : T);
};
vector<int> A(N + 1); for (int i = 0; i <= N; i++) {
cin >> A[i];
if (i) segtree.update(1, 1, N, i, i, A[i]), curr += cal(A[i - 1], A[i]);
}
while (Q-- > 0) {
int64_t L, R, X; cin >> L >> R >> X;
int el1 = segtree.getans(1, 1, N, L - 1, L - 1), el2 = segtree.getans(1, 1, N, L, L);
if (L - 1 >= 0) curr -= cal(el1, el2);
el1 = segtree.getans(1, 1, N, R, R), el2 = segtree.getans(1, 1, N, R + 1, R + 1);
if (R + 1 <= N) curr -= cal(el1, el2);
segtree.update(1, 1, N, L, R, X);
el1 = segtree.getans(1, 1, N, L - 1, L - 1), el2 = segtree.getans(1, 1, N, L, L);
if (L - 1 >= 0) curr += cal(el1, el2);
el1 = segtree.getans(1, 1, N, R, R), el2 = segtree.getans(1, 1, N, R + 1, R + 1);
if (R + 1 <= N) curr += cal(el1, el2);
cout << curr << '\n';
}
return 0;
}
