#include<bits/stdc++.h> #define ll long long #define int long long #define maxn 500005 #define fi first #define se second #define sti string using namespace std; ll n,a[maxn],q,S,T; ll calc(ll Diff){ if(Diff>0) return -S*Diff; else return -T*Diff; } ll diff[maxn]; signed main () { ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); cin>>n>>q>>S>>T; for(int i=0;i<=n;i++) cin>>a[i]; for(int i=1;i<=n;i++) diff[i]=a[i]-a[i-1]; ll res=0; for(int i=1;i<=n;i++) res+=calc(diff[i]); while(q--){ int L,R,x; cin>>L>>R>>x; if(L>=1 && L<=n){ res-=calc(diff[L]); diff[L]+=x; res+=calc(diff[L]); } R++; if(R>=1 && R<=n){ res-=calc(diff[R]); diff[R]-=x; res+=calc(diff[R]); } cout<<res<<'\n'; } return 0; }