#include <bits/stdc++.h>
#include <chrono>
using namespace std;
using namespace std::chrono;
// #pragma GCC target ("avx2")
// #pragma GCC optimization ("O3")
// #pragma GCC optimization ("unroll-loops")
#define f0r(a, b) for (long long a = 0; a < b; a++)
#define f1r(a, b, c) for (long long a = b; a < c; a++)
#define f0rd(a, b) for (long long a = b; a >= 0; a--)
#define f1rd(a, b, c) for (long long a = b; a >= c; a--)
#define ms(arr, v) memset(arr, v, sizeof(arr))
#define pb push_back
#define io {ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);}
#define mp make_pair
#define f first
#define s second
#define presum(p, a, n) {p[0] = a[0]; for (int i = 1; i < n; i++) p[i] = a[i] + p[i-1];}
#define all(v) v.begin(), v.end()
#define readgraph(list, edges) for (int i = 0; i < edges; i++) {int a, b; cin >> a >> b; a--; b--; list[a].pb(b); list[b].pb(a);}
#define ai(a, n) for (int ele = 0; ele < n; ele++) cin >> a[ele];
#define ain(a, lb, rb) for (int ele = lb; ele <= rb; ele++) cin >> a[ele];
#define ao(a, n) {for (int ele = 0; ele < n; ele++) { if (ele) cout << " "; cout << a[ele]; } cout << '\n';}
#define aout(a, lb, rb) {for (int ele = lb; ele <= rb; ele++) { if (ele > lb) cout << " "; cout << a[ele]; } cout << '\n';}
typedef long long ll;
typedef double ld;
typedef long double lld;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
template<typename A, typename B> ostream& operator<<(ostream &cout, pair<A, B> const &p) { return cout << "(" << p.f << ", " << p.s << ")"; }
template<typename A> ostream& operator<<(ostream &cout, vector<A> const &v) {
cout << "["; for(int i = 0; i < v.size(); i++) {if (i) cout << ", "; cout << v[i];} return cout << "]";
}
// template<typename A, typename B> ll max(A x, B y) {
// return x > y ? x : y;
// }
// template<typename A, typename B> ll min(A x, B y) {
// return x < y ? x : y;
// }
mt19937 rng(steady_clock::now().time_since_epoch().count());
/* usage - just do rng() */
void usaco(string filename) {
#pragma message("be careful, freopen may be wrong")
freopen((filename + ".in").c_str(), "r", stdin);
freopen((filename + ".out").c_str(), "w", stdout);
}
const ll mod = 1000000007;
ll madd(ll a, ll b) {
return (a + b) % mod;
}
ll msub(ll a, ll b) {
return (((a - b) % mod) + mod) % mod;
}
ll mmul(ll a, ll b) {
return ((a % mod) * (b % mod)) % mod;
}
ll mpow(ll base, ll exp) {
ll res = 1;
while (exp) {
if (exp % 2 == 1){
res = (res * base) % mod;
}
exp >>= 1;
base = (base * base) % mod;
}
return res;
}
ll minv(ll base) {
return mpow(base, mod - 2);
}
ll mdiv(ll a, ll b) {
return mmul(a, minv(b));
}
ll gcd(ll x, ll y) {
if (x == 0) return y;
if (y == 0) return x;
return gcd(y, x % y);
}
bool prime[1000006];
void sieve(int n) {
f0r(i, n + 1) prime[i] = 1;
for (int p = 2; p * p <= n; p++) {
if (prime[p] == true) {
for (int i = p * p; i <= n; i += p)
prime[i] = false;
}
}
prime[1] = prime[0] = 0;
}
template <typename num_t>
struct segtree {
int n, depth;
vector<num_t> tree, lazy;
void init(int s, int* arr) {
n = s;
tree = vector<num_t>(4 * s, 0);
lazy = vector<num_t>(4 * s, 0);
init(0, 0, n - 1, arr);
}
num_t init(int i, int l, int r, int* arr) {
if (l == r) return tree[i] = arr[l];
int mid = (l + r) / 2;
num_t a = init(2 * i + 1, l, mid, arr),
b = init(2 * i + 2, mid + 1, r, arr);
return tree[i] = a.op(b);
}
void update(int l, int r, num_t v) {
if (l > r) return;
update(0, 0, n - 1, l, r, v);
}
num_t update(int i, int tl, int tr, int ql, int qr, num_t v) {
eval_lazy(i, tl, tr);
if (ql <= tl && tr <= qr) {
lazy[i] = lazy[i].val + v.val;
eval_lazy(i, tl, tr);
return tree[i];
}
if (tl > tr || tr < ql || qr < tl) return tree[i];
if (tl == tr) return tree[i];
int mid = (tl + tr) / 2;
num_t a = update(2 * i + 1, tl, mid, ql, qr, v),
b = update(2 * i + 2, mid + 1, tr, ql, qr, v);
return tree[i] = a.op(b);
}
num_t query(int l, int r) {
if (l > r) return num_t::null_v;
return query(0, 0, n-1, l, r);
}
num_t query(int i, int tl, int tr, int ql, int qr) {
eval_lazy(i, tl, tr);
if (ql <= tl && tr <= qr) return tree[i];
if (tl > tr || tr < ql || qr < tl) return num_t::null_v;
int mid = (tl + tr) / 2;
num_t a = query(2 * i + 1, tl, mid, ql, qr),
b = query(2 * i + 2, mid + 1, tr, ql, qr);
return a.op(b);
}
void eval_lazy(int i, int l, int r) {
tree[i] = tree[i].lazy_op(lazy[i], (r - l + 1));
if (l != r) {
lazy[i * 2 + 1] = lazy[i].val + lazy[i * 2 + 1].val;
lazy[i * 2 + 2] = lazy[i].val + lazy[i * 2 + 2].val;
}
lazy[i] = num_t();
}
};
struct max_t {
long long val;
static const long long null_v = -9223372036854775807LL;
max_t(): val(0) {}
max_t(long long v): val(v) {}
max_t op(max_t& other) {
return max_t(max(val, other.val));
}
max_t lazy_op(max_t v, int size) {
return max_t(val + v.val);
}
};
ll n, m, k, q, Q, T, l, r, x, y, z;
int a[500005];
int b[500005];
string s, t;
ll ans = 0;
segtree<max_t> st;
int main() {
io;
// freopen("case", "r", stdin);
// freopen("test.txt", "r", stdin);
// freopen("case", "w", stdout);
// usaco("file");
cin >> n >> q >> x >> y;
n++;
ai(a, n);
f0r(i, n - 1) {
if (a[i] < a[i + 1]) ans -= x * (a[i + 1] - a[i]);
else ans -= y * (a[i + 1] - a[i]);
}
st.init(n, a);
f0r(i, q) {
cin >> l >> r >> z;
ll leftl = st.query(l - 1, l - 1).val, leftr = st.query(l, l).val;
if (leftl < leftr) ans += x * (leftr - leftl);
else ans += y * (leftr - leftl);
leftr += z;
if (leftl < leftr) ans -= x * (leftr - leftl);
else ans -= y * (leftr - leftl);
if (r != n - 1) {
ll rightl = st.query(r, r).val, rightr = st.query(r + 1, r + 1).val;
if (rightl < rightr) ans += x * (rightr - rightl);
else ans += y * (rightr - rightl);
rightl += z;
if (rightl < rightr) ans -= x * (rightr - rightl);
else ans -= y * (rightr - rightl);
}
st.update(l, r, z);
cout << ans << '\n';
}
}
