#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define popcount __builtin_popcount
#define all(a) (a).begin(), (a).end()
using namespace std;
using namespace chrono;
using namespace __gnu_pbds;
template<typename T> using ordered_set = tree<T,null_type,less_equal<>,rb_tree_tag,tree_order_statistics_node_update>;
int get_pos(vector<pair<int,int>>& A, int i, int j) {
return ranges::find(A, pair{i, j}) - A.begin();
}
vector<vector<int>> Azzurro(int n, int l, string s) {
s += string(51 - l, 'A');
vector<pair<int,int>> diag[15];
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
diag[i + j].emplace_back(i, j);
}
}
vector<vector<int>> G(n, vector<int>(n));
int p = 0;
for (int d = 0; d < 15; d++) {
if (diag[d].size() == 1) {
G[ diag[d][0].first ][ diag[d][0].second ] = s[p++] - 'A';
continue;
}
auto [si, sj] = diag[d][0];
for (int k = 1; k < diag[d].size(); k++) {
auto [i, j] = diag[d][k];
G[i][j] = s[p++] - 'A';
if (k % 2 == 0)
G[si][sj] ^= G[i][j];
}
}
return G;
}
string Bordeaux(int n, int l, vector<vector<int>> G) {
string s = string(1, 'B' - G[0][0]);
vector<pair<int,int>> diag[15];
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
diag[i + j].emplace_back(i, j);
}
}
int pi = 0, pj = 0;
for (int d = 1; d < 15; d++) {
int x = 0;
for (int k = 0; k < diag[d].size(); k += 2) {
auto [i, j] = diag[d][k];
x ^= G[i][j];
}
int flip = x^1;
int ni = pi, nj = pj;
if (pi+1 < n && get_pos(diag[d], pi + 1, pj) % 2 == flip % 2) {
ni++;
} else {
nj++;
}
for (int k = 1; k < diag[d].size(); k++) {
auto [i, j] = diag[d][k];
if (i == ni && j == nj) G[i][j] ^= 1;
s += 'A' + G[i][j];
}
pi = ni, pj = nj;
}
s += 'B' - G[n-1][n-1];
return s.substr(0, l);
}
int main() {
int n, q, s, t; cin >> n >> q >> s >> t;
int A[n+1];
long long D[n];
cin >> A[0];
for (int i = 0; i < n; i++) {
cin >> A[i+1];
D[i] = A[i+1] - A[i];
}
long long ans = 0;
auto add = [&](int i) { ans += abs(D[i])*(D[i] > 0 ? -s : t); };
auto rem = [&](int i) { ans -= abs(D[i])*(D[i] > 0 ? -s : t); };
auto update = [&](int i, int x) {
if (i == n) return;
rem(i);
D[i] += x;
add(i);
};
for (int i = 0; i < n; i++) add(i);
while (q--) {
int l,r,x; cin >> l >> r >> x;
update(l-1, x);
update(r, -x);
cout<<ans<<"\n";
}
}
