#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;
template <class T>
void read(T &x)
{
x = 0;
register int c;
while ((c = getchar()) && (c > '9' || c < '0'))
;
for (; c >= '0' && c <= '9'; c = getchar())
x = x * 10 + c - '0';
}
constexpr bool typetest = 0;
constexpr int N = 2e5 + 5;
struct SegmentTree
{
int n;
ll st[N * 4];
SegmentTree()
{
memset(st, 0, sizeof st);
}
void Push(int id)
{
if (st[id])
{
st[id << 1] += st[id];
st[id << 1 | 1] += st[id];
st[id] = 0;
}
}
void Build(int id, int l, int r, ll a[N])
{
if (l == r)
{
st[id] = a[l];
return;
}
Build(id << 1, l, (l + r) / 2, a);
Build(id << 1 | 1, (l + r) / 2 + 1, r, a);
}
void Build(ll a[N])
{
Build(1, 1, n, a);
}
void Update(int id, int l, int r, const int &a, const int &b, const ll &v)
{
if (l > b || r < a)
return;
if (l >= a && r <= b)
{
st[id] += v;
return;
}
Push(id);
Update(id << 1, l, (l + r) / 2, a, b, v);
Update(id << 1 | 1, (l + r) / 2 + 1, r, a, b, v);
}
void Update(int l, int r, ll v)
{
Update(1, 1, n, l, r, v);
}
ll Get(int x)
{
int l = 1, r = n, id = 1;
while (1)
{
if (l == r)
break;
Push(id);
if ((l + r) / 2 >= x)
{
id = id << 1;
r = (l + r) / 2;
}
else
{
id = id << 1 | 1;
l = (l + r) / 2 + 1;
}
}
return st[id];
}
} f;
int n, q;
ll s, t, a[N], ans;
void Read()
{
cin >> n >> q >> s >> t;
for (int i = 0; i <= n; ++i)
cin >> a[i];
}
void Remove(int l, int r)
{
if (r > n)
return;
ll u = l == 0 ? 0 : f.Get(l),
v = f.Get(r);
if (u < v)
ans += (v - u) * s;
else
ans -= (u - v) * t;
}
void Add(int l, int r)
{
if (r > n)
return;
ll u = l == 0 ? 0 : f.Get(l),
v = f.Get(r);
// cerr << l << " " << r << ": " << u << " " << v << "\n";
if (u < v)
ans -= (v - u) * s;
else
ans += (u - v) * t;
}
void Solve()
{
f.n = n;
f.Build(a);
for (int i = 1; i <= n; ++i)
{
Add(i - 1, i);
// cout << i << ": " << ans << "\n";
}
while (q--)
{
int l, r, x;
cin >> l >> r >> x;
Remove(l - 1, l);
Remove(r, r + 1);
f.Update(l, r, x);
Add(l - 1, l);
Add(r, r + 1);
cout << ans << '\n';
}
}
int32_t main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
if (fopen("tests.inp", "r"))
{
freopen("test.inp", "r", stdin);
freopen("test.out", "w", stdout);
}
int t(1);
if (typetest)
cin >> t;
for (int _ = 1; _ <= t; ++_)
{
// cout << "Case " << _ << ": ";
Read();
Solve();
}
cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
}
/*
*/
