#include <bits/stdc++.h> using namespace std; using ll = long long; #define int ll using P = pair<int, int>; #define all(x) x.begin(), x.end() #define rep(i, l, n) for (int i = l; i < (n); ++i) #define sz(x) (int)x.size() const char nl = '\n'; const int mod = 1e9+7; struct node { int v, w, k; }; void solve() { int n, q, s, t; cin >> n >> q >> s >> t; vector<int> a(n+1); for (auto &i: a)cin >> i; while (q--) { int l, r, x; cin >> l >> r >> x; rep(i, l, r+1)a[i] += x; int cur = 0; rep(i, 1, n+1) { if (a[i-1] >= a[i])cur += (a[i-1]-a[i])*t; else cur -= (a[i]-a[i-1])*s; } cout << cur << nl; } } int32_t main() { ios_base::sync_with_stdio(0); cin.tie(0); solve(); return 0; }