#include<bits/stdc++.h>
using namespace std;
constexpr int sz = 200005;
int N, Q, S, T, A[sz];
long long sm, Temp[sz], tree[sz << 2], lazy[sz << 2];
inline void build(int l, int r, int node){
if(l == r){
tree[node] = A[l];
return;
}
int mid = l + ((r - l) >> 1);
build(l, mid, node << 1);
build(mid + 1, r, node << 1 | 1);
tree[node] = tree[node << 1] + tree[node << 1 | 1];
return;
}
inline void relax(int node, int l, int r){
if(l != r){
lazy[node << 1] += lazy[node];
lazy[node << 1 | 1] += lazy[node];
}
tree[node] += 1ll * (r - l + 1) * lazy[node];
lazy[node] = 0ll;
return;
}
inline void update(int l, int r, int node, int L, int R, int val){
if(lazy[node]) relax(node, l, r);
if(l > R || r < L || r < l) return;
if(l >= L && r <= R){
lazy[node] += val;
relax(node, l, r);
return;
}
int mid = l + ((r - l) >> 1);
update(l, mid, node << 1, L, R, val);
update(mid + 1, r, node << 1 | 1, L, R, val);
tree[node] = tree[node << 1] + tree[node << 1 | 1];
return;
}
long long get_ans(int l, int r, int node, int L, int R){
if(l > R || r < L || r < l) return 0ll;
if(lazy[node]) relax(node, l, r);
if(l >= L && r <= R) return tree[node];
int mid = l + ((r - l) >> 1);
return get_ans(l, mid, node << 1, L, R) + get_ans(mid + 1, r, node << 1 | 1, L, R);
}
signed main(){
ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
cin >> N >> Q >> S >> T;
for(register int i = 0; i <= N; ++i) cin >> A[i];
build(1, N, 1);
function<void(int, long long)> Update = [&](int pos, long long val){
if(!(pos >= 1 && pos <= N)) return;
sm -= Temp[pos];
if(val < 0){
Temp[pos] = 1ll * val * S;
}else{
Temp[pos] = 1ll * val * T;
}
sm += Temp[pos];
};
for(register int i = 1; i <= N; ++i) Update(i, A[i - 1] - A[i]);
int L, R, X;
while(Q--){
cin >> L >> R>> X;
update(1, N, 1, L, R, X);
Update(L, get_ans(1, N, 1, L - 1, L - 1) - get_ans(1, N, 1, L, L));
Update(R + 1, get_ans(1, N, 1, R, R) - get_ans(1, N, 1, R + 1, R + 1));
cout << sm << '\n';
}
return 0;
}
