#include<bits/stdc++.h>
#include<queue>
#include<string.h>
#include<iostream>
#include<map>
#include<vector>
#include<algorithm>
#define int long long
#define ll long long
#define rep(i,a,b) for(int i=a;i<=b;i++)
#define nl t[n].l
#define nr t[n].r
#define gcd __gcd
#define itn int
#define db long double
using namespace std;
const int maxn=3e6+50;
const int inf=1e18+10;
const int INF=2e18;
const int mod=998244353;
//const db eps=1e-8;
//const db pi=acos(-1.0);
#define pop_count __builtin_popcountll
int f[maxn];
int s[maxn],w[maxn],d[maxn];
int t[maxn];
void solve(){
    int n,m,c;
    cin>>n>>m>>c;
    rep(i,1,n) cin>>s[i];
    rep(i,1,m)
    {
        cin>>w[i]>>d[i]>>t[i];
    }
    rep(i,1,n) f[i]=inf;
    rep(i,0,n-1)
    {
        f[i+1]=min(f[i+1],f[i]+s[i+1]*c);
        rep(j,1,m)
        {
            int tot=0;
            int lim=min(n,i+d[j]);
            rep(k,i+1,lim)
            {
                tot+=max(0ll,s[k]-t[j])*c;
                f[k]=min(f[k],f[i]+tot+w[j]);
            }
        }
    }
    cout<<f[n];

}


signed main()
{
   ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
   int __=1;
   srand((time(0)));
  // cin>>__;
  while(__--)
  {
       solve();
  }
    return 0;
}