#include <algorithm>
#include <iostream>
#include <numeric>
#include <vector>
typedef long long llong;
const int MAXN = 200000 + 10;
llong n, q, s, t;
int a[MAXN];
struct Node
{
llong left, right;
llong sum, lazy;
Node()
{
left = right = sum = lazy = 0;
}
} tree[4*MAXN];
Node combine(Node left, Node right)
{
Node res;
res.left = left.left;
res.right = right.right;
res.sum = left.sum + right.sum;
if (left.right <= right.left) res.sum -= s * (right.left - left.right);
else res.sum += t * (left.right - right.left);
return res;
}
void build(int l, int r, int node)
{
if (l == r)
{
tree[node].left = a[l];
tree[node].right = a[l];
tree[node].lazy = 0;
tree[node].sum = 0;
return;
}
int mid = (l + r) / 2;
build(l, mid, 2*node);
build(mid + 1, r, 2*node + 1);
tree[node] = combine(tree[2*node], tree[2*node + 1]);
}
void push(int node, int l, int r)
{
if (tree[node].lazy == 0) return;
tree[node].left += tree[node].lazy;
tree[node].right += tree[node].lazy;
if (l < r)
{
tree[2*node].lazy += tree[node].lazy;
tree[2*node + 1].lazy += tree[node].lazy;
}
tree[node].lazy = 0;
}
void update(int l, int r, int node, int queryL, int queryR, int queryVal)
{
push(node, l, r);
if (queryR < l || r < queryL) return;
if (queryL <= l && r <= queryR)
{
tree[node].lazy = queryVal;
push(node, l, r);
return;
}
int mid = (l + r) / 2;
update(l, mid, 2*node, queryL, queryR, queryVal);
update(mid + 1, r, 2*node + 1, queryL, queryR, queryVal);
tree[node] = combine(tree[2*node], tree[2*node + 1]);
}
void solve()
{
int l, r, value;
build(0, n, 1);
for (int i = 1 ; i <= q ; ++i)
{
std::cin >> l >> r >> value;
update(0, n, 1, l, r, value);
std::cout << tree[1].sum << '\n';
}
}
void read()
{
std::cin >> n >> q >> s >> t;
for (int i = 0 ; i <= n ; ++i)
{
std::cin >> a[i];
}
}
void fastIO()
{
std::ios_base :: sync_with_stdio(0);
std::cout.tie(nullptr);
std::cin.tie(nullptr);
}
int main()
{
fastIO();
read();
solve();
return 0;
}
