#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
//#include<bits/extc++.h>
//__gnu_pbds
int main(){
ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0);
int n,q,s,t;cin>>n>>q>>s>>t;
ll dif[n+1]={0};
int a;cin>>a;
ll sum = 0;
for(int i=1;i<=n;i++){
int b;cin>>b;
dif[i] = b-a;
sum+=1LL*((dif[i]<0)?(t):(-s))*abs(dif[i]);
a = b;
}
while(q--){
int l,r,k;cin>>l>>r>>k;
r++;
sum-=1LL*((dif[l]<0)?(t):(-s))*abs(dif[l]);
dif[l]+=k;
sum+=1LL*((dif[l]<0)?(t):(-s))*abs(dif[l]);
if(r<=n){
sum-=1LL*((dif[r]<0)?(t):(-s))*abs(dif[r]);
dif[r]-=k;
sum+=1LL*((dif[r]<0)?(t):(-s))*abs(dif[r]);
}
cout<<sum<<"\n";
}
return 0;
}
