#include <iostream>
#include <string>
#include <vector>
#include <set>
#include <queue>
#include <stack>
#include <map>
#include <algorithm>
#include <math.h>
#include <cassert>
#define rep(i,n) for(int i = 0; i < n; ++i )
using namespace std;
using ll = long long;
using P = pair<int,int>;

int main() {
  ll n,a,b;
  cin >> n >> a >> b;
  vector<ll> x(n);
  rep(i,n) cin >> x[i];

  ll ans = 0;
  rep(i,n-1) ans += min((x[i+1]-x[i])*a,b);
  cout << ans << endl;
}
#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
  int N,A,B,n;
  cin>>N>>A>>B>>n;
  vector<int> C(N);
  C[0]=n;
  int ans=0;
  for(int i=1;i<N;i++){
    cin>>C[i];
    ans+=min((C[i]-C[i-1])*A,B);
  }
  cout<<ans<<endl;
}