#include <bits/stdc++.h>
using namespace std;
using ll=long long;
const int MAX=2*1e5+7;
const int base=1<<20;
ll drzewo[2*base];
void ppush(int a, int b, ll w){
a += base-1;
b += base+1;
while (a/2!=b/2){
if (a%2==0) drzewo[a+1]+=w;
if (b%2==1) drzewo[b-1]+=w;
a/=2;
b/=2;
}
}
void get(int a){
int a2=a;
a+=base;
ll wyn=0;
while (a>0){
wyn += drzewo[a];
a /= 2;
}
drzewo[base+a2] = wyn;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int n, q, l, r;
ll s, t, x, wyn=0;
cin >> n >> q >> s >> t;
cin >> drzewo[base];
for (int i=1; i<=n; i++){
cin >> drzewo[base+i];
if (drzewo[base+i-1] < drzewo[base+i]) wyn -= s*(drzewo[base+i]-drzewo[base+i-1]);
else wyn += t*(drzewo[base+i-1]-drzewo[base+i]);
}
for (int i=0; i<q; i++){
cin >> l >> r >> x;
//cout << wyn << endl;
if (drzewo[base+l-1] < drzewo[base+l]) wyn += s*(drzewo[base+l]-drzewo[base+l-1]);
else wyn -= t*(drzewo[base+l-1]-drzewo[base+l]);
if (r!=n){
if (drzewo[base+r] < drzewo[base+r+1]) wyn += s*(drzewo[base+r+1]-drzewo[base+r]);
else wyn -= t*(drzewo[base+r+1]-drzewo[base+r]);
}
//cout << wyn << endl;
ppush(l, r, x);
get(l);
get(r);
if (drzewo[base+l-1] < drzewo[base+l]) wyn -= s*(drzewo[base+l]-drzewo[base+l-1]);
else wyn += t*(drzewo[base+l-1]-drzewo[base+l]);
if (r!=n){
if (drzewo[base+r] < drzewo[base+r+1]) wyn -= s*(drzewo[base+r+1]-drzewo[base+r]);
else wyn += t*(drzewo[base+r+1]-drzewo[base+r]);
}
cout << wyn << "xd\n";
}
return 0;
}
