#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template<typename T>
using order_set = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
#define ar array
#define ld long double
#define all(v) v.begin(), v.end()
#define int long long
#pragma GCC optimize("unroll-loops,O3,Ofast")
const int inf = 1e15 + 20;
const int maxN = 4e5 + 20;
signed main(){ios_base::sync_with_stdio(false);cin.tie(0);
int n, q, s, t;
cin>>n>>q>>s>>t;
int A[n];
int prv;
cin>>prv;
for(int i = 0;i < n;i++){
int x;
cin>>x;
A[i] = prv - x;
prv = x;
}
int ans = 0;
for(int i = 0;i < n;i++){
if(A[i] > 0)ans += t * A[i];
else ans += s * A[i];
}
while(q--){
int l, r, v;
cin>>l>>r>>v;
--l;
if(A[l] >= 0)ans -= t * A[l];
else ans -= s * A[l];
A[l] -= v;
if(A[l] >= 0)ans += t * A[l];
else ans += s * A[l];
if(r < n){
if(A[r] >= 0)ans -= t * A[r];
else ans -= s * A[r];
A[r] += v;
if(A[r] >= 0)ans += t * A[r];
else ans += s * A[r];
}
cout<<ans<<'\n';
}
}
