#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define db double
#define ll __int128
#define int long long
#define pb push_back
#define fs first
#define sd second
#define Mod long(1e9 + 7)
#define all(x) x.begin(), x.end()
#define unvisited long(-1)
#define Eps double(1e-9)
#define _for(i, n) for(int i = 0; i < (n); i++)
#define dbg(x) cout << #x ": " << x << endl;
const int Max = 1e6 + 7, Inf = 1e9 + 7;
void print(bool x) { cout << (x ? "YES" : "NO") << endl; }
string tostring (__int128 x)
{
string ans = "";
while(x > 0)
{
ans += (x % 10 + '0');
x /= 10;
}
reverse(all(ans));
return ans;
}
int ans = 0, n, q, s, t;
int f(int a, int b)
{
if(a < b)
return (a - b) * s;
else
return (a - b) * t;
}
struct SQRT
{
vector <int> block, sec; int sqrt_n;
void update(int l, int r, int v)
{
ans -= f(block[((l - 1) / sqrt_n)] + sec[l - 1], block[((l) / sqrt_n)] + sec[l]);
if(r != n) ans -= f(block[((r) / sqrt_n)] + sec[r], block[((r + 1) / sqrt_n)] + sec[r + 1]);
for(int i = l; i <= r; i++)
{
if((i % sqrt_n == 0) && (i + sqrt_n <= r))
block[(i / sqrt_n)] += v, i += sqrt_n - 1;
else
sec[i] += v;
}
ans += f(block[((l - 1) / sqrt_n)] + sec[l - 1], block[((l) / sqrt_n)] + sec[l]);
if(r != n) ans += f(block[((r) / sqrt_n)] + sec[r], block[((r + 1) / sqrt_n)] + sec[r + 1]);
}
SQRT(int n)
{
sqrt_n = sqrt(n) + 1;
block.assign(sqrt_n + 7, 0);
sec.assign(n + 7, 0);
}
};
void solve()
{
cin >> n >> q >> s >> t;
vector <int> v(n+1);
for(auto& u : v) cin >> u;
SQRT St(n+7);
for(int i = 1; i <= n; i++)
St.update(i, i, v[i]);
while (q--)
{
int l, r, x; cin >> l >> r >> x;
St.update(l, r, x);
cout << ans << endl;
}
}
int32_t main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int Q = 1; //cin >> Q;
while (Q--)
{
solve();
}
return 0;
}
