#include <bits/stdc++.h>
using namespace std;
#define int long long
#define form2(i, a, b) for (int i = (a); i < (b); ++i)
#define ford2(i, a, b) for (int i = (a-1); i >= b; --i)
#define form(i, n) form2(i, 0, n)
#define ford(i, n) ford2(i, n, 0)
#define chmax(x, v) x = max(x, (v))
#define chmin(x, v) x = min(x, (v))
#define fi first
#define se second
const long long BIG = 1000000000000000000LL;
typedef long long ll;
typedef long double ld;
void cpr(string s, vector<int> v)
{ int i = 0; for (char c : s) { if (c == '$') cout << v[i++]; else cout << c; } cout << '\n'; }
void cpr(string s) { cpr(s, {}); }
void solve();
signed main()
{
ios::sync_with_stdio(false);
cin.tie(0);
solve();
return 0;
}
const int borne = 201*1000;
int nbMaisons, nbReq, mont, desc;
int deltas[borne];
int curTemp = 0;
void add(int i, int x)
{
int avant = deltas[i];
int apres = avant+x;
if (avant < 0) {
curTemp -= mont*avant;
} else {
curTemp -= desc*avant;
}
if (apres < 0) {
curTemp += mont*apres;
} else {
curTemp += desc*apres;
}
deltas[i] = apres;
}
void solve()
{
cin >> nbMaisons >> nbReq >> mont >> desc;
int prev = 0;
cin >> prev;
form(i, nbMaisons) {
int alt;
cin >> alt;
deltas[i] = -(alt - prev);
prev = alt;
}
form(i, nbMaisons) {
if (deltas[i] < 0) { // a[i] < a[i+1]
curTemp += mont*deltas[i];
} else {
curTemp += desc*deltas[i];
}
}
form(i, nbReq) {
int l, r, x;
cin >> l >> r >> x;
if (l != 0) add(l-1, -x);
if (r != nbMaisons) add(r, x);
cout << curTemp << "\n";
}
}
