#include <stdio.h>
#include <vector>
#include <algorithm>
using namespace std;
#define F first
#define S second
#define mp make_pair
#define pb push_back
#define ll long long int
#define ieps 200010
#define eps (int) 1e9
#define pii pair<int,int>
struct node{
ll leftmost, rightmost, sumup , sumdown;
void clv(){
leftmost = rightmost = sumup = sumdown = 0;
}
};
int a , b , val;
int n , q , v[200100] ;
ll s , t;
ll lazy[560000];
node st[560000];
void propagate(int curr , int l , int r){
if(lazy[curr]){
st[curr].leftmost += lazy[curr];
st[curr].rightmost += lazy[curr];
if(l != r){
lazy[2*curr] += lazy[curr];
lazy[2*curr + 1] += lazy[curr];
}
lazy[curr] = 0;
}
return;
}
node mixnode(node left, node right){
node x;
x.clv();
ll toadd = 0 , tosubtract = 0;
if(left.rightmost >= right.leftmost){
toadd += t*(left.rightmost - right.leftmost);
}
else if(left.rightmost < right.leftmost){
tosubtract += s*(right.leftmost - left.rightmost);
}
x.leftmost = left.leftmost;
x.rightmost = right.rightmost;
x.sumup = left.sumup + right.sumup + toadd;
x.sumdown = left.sumdown + right.sumdown + tosubtract;
return x;
}
void build(int l = 0 , int r = n- 1 , int curr = 1){
if(l == r){
st[curr].clv();
st[curr].rightmost = st[curr].leftmost = v[l];
return;
}
build(l , (l+r)/2 , 2*curr);
build((l+r)/2 + 1 , r, 2*curr + 1);
st[curr] = mixnode(st[2*curr] , st[2*curr + 1]);
return;
}
void update(int x , int y , int l = 0 , int r = n- 1 , int curr = 1){
propagate(curr, l , r);
if(l == x && r == y){
lazy[curr]+=val;
propagate(curr, l , r);
return;
}
ll mid = (l+r)/2;
if(y <= mid){
update(x , y, l , mid , 2*curr);
}
else if(x > mid){
update(x ,y, mid + 1 ,r , 2*curr + 1);
}
else{
update(x , mid , l , mid , 2*curr);
update(mid + 1 , y , mid + 1 , r , 2*curr + 1);
}
propagate(2*curr , l , mid);
propagate(2*curr + 1 , mid + 1 , r);
st[curr] = mixnode(st[2*curr] , st[2*curr + 1]);
return;
}
int main(){
scanf("%d %d %lld %lld", &n, &q, &s, &t);
n = n+1;
for(int i = 0;i<n;i++) scanf("%d", &(v[i]));;
build();
for(int i = 0;i<q;i++){
scanf("%d%d%d", &a, &b, &val);
update(a , b);
ll p = st[1].sumup;
p-=st[1].sumdown;
printf("%lld\n",p);
}
return 0;
}
