#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define st first
#define nd second
typedef long long ll;
typedef long double ld;
const ll I = 1000'000'000'000'000'000LL;
const int II = 2'000'000'000;
const ll M = 1000'000'007LL;
const int N = 1000'007;
ll dif[N];
ll ans = 0LL;
ll S, T;
void A(int i, ll r)
{
if(dif[i] > 0) ans -= (dif[i] * S) * r;
if(dif[i] < 0) ans -= (dif[i] * T) * r;
}
void Solve()
{
int n, q;
cin >> n >> q >> S >> T;
int p = 0, c;
cin >> p;
for(int i = 1; i <= n; ++i)
{
cin >> c;
dif[i] = c - p;
A(i, 1LL);
p = c;
}
int a, b; ll x;
for(int i = 1; i <= q; ++i)
{
cin >> a >> b >> x;
A(a, -1LL); A(b + 1, -1LL);
dif[a] += x;
if(b < n)
dif[b + 1] -= x;
A(a, 1LL); A(b + 1, 1LL);
cout << ans << "\n";
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
//int t; cin >> t;
//while(t--)
Solve();
return 0;
}
