// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx")
#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <unordered_map>
#include <set>
#include <map>
#include <queue>
#include <random>
#include <chrono>
#define fi first
#define se second
#define pb push_back
#define ll long long
#define ld long double
#define hm unordered_map
#define pii pair<int, int>
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define cinv(v) for (auto& x: v) cin >> x
#define fr(i, n) for (int i = 0; i < n; ++i)
#define fl(i, l, n) for (int i = l; i < n; ++i)
#define int ll
template <typename T1, typename T2> inline bool chkmin(T1 &x, const T2 &y) {if (x > y) {x = y; return 1;} return 0;}
template <typename T1, typename T2> inline bool chkmax(T1 &x, const T2 &y) {if (x < y) {x = y; return 1;} return 0;}
using namespace std;
#ifdef LOCAL
#define dbg(x) cerr << #x << " : " << x << '\n'
#else
#define dbg(x)
#endif
//tg: @runningcherry
template <typename T1, typename T2> ostream& operator << (ostream& out, const pair<T1, T2>& v) {
out << v.fi << ", " << v.se;
return out;
}
template<typename T> ostream& operator << (ostream& out, const vector<T>& v) {
for (auto& x: v) out << x << " ";
return out;
}
template <typename T1, typename T2> ostream& operator << (ostream& out, const map<T1, T2>& v) {
for (auto& x: v) out << x << '\n';
return out;
}
template<typename T> ostream& operator << (ostream& out, const set<T>& v) {
for (auto& x: v) out << x << " ";
return out;
}
template<typename T> ostream& operator << (ostream& out, const multiset<T>& v) {
for (auto& x: v) out << x << " ";
return out;
}
template <typename T1, typename T2> istream& operator >> (istream& in, pair<T1, T2>& a) {
in >> a.fi >> a.se;
return in;
}
const ll inf = (ll) 2e9;
const ld pi = asin (1) * 2;
const ld eps = 1e-8;
const ll mod = (ll)1e9 + 7;
const ll ns = 97;
const int maxn = 2e5 + 20;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
struct fenw {
vector<int> t;
fenw (int n) {
t = vector<int> (n);
}
inline void add (int i, int x) {
for (; i < sz (t); i += i & -i) t[i] += x;
}
inline int get (int i) {
int ans = 0;
for (; i > 0; i -= i & -i) ans += t[i];
return ans;
}
};
signed main () {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n, q, s, t;
cin >> n >> q >> s >> t;
vector<int> goo (n + 1);
cinv (goo);
fenw fen (n + 10);
int res = 0;
fl (i, 1, n + 1) {
fen.add (i, goo[i] - goo[i - 1]);
if (goo[i - 1] < goo[i]) {
res -= s * (goo[i] - goo[i - 1]);
} else {
res += t * (goo[i - 1] - goo[i]);
}
}
dbg (res);
while (q--) {
int l, r, x;
cin >> l >> r >> x;
int a = fen.get (l - 1);
int b = fen.get (l);
if (a < b) res += s * (b - a);
else res -= t * (a - b);
if (r != n) {
a = fen.get (r);
b = fen.get (r + 1);
if (a < b) res += s * (b - a);
else res -= t * (a - b);
}
fen.add (l, x);
fen.add (r + 1, -x);
a = fen.get (l - 1);
b = fen.get (l);
if (a < b) res -= s * (b - a);
else res += t * (a - b);
if (r != n) {
a = fen.get (r);
b = fen.get (r + 1);
if (a < b) res -= s * (b - a);
else res += t * (a - b);
}
cout << res << '\n';
}
}
